Readers can tell a self-published book from a traditionally published one within seconds of opening it. Not because of the writing. Because of the formatting. There’s a specific set of formatting decisions — maybe a dozen of them — that separate “professionally produced” from “did this in Word over a weekend.”
The good news: every one of these mistakes is fixable. Most are easy to fix once you know what to look for. Here are the twelve most common formatting mistakes in self-published books, why they matter, and how to get each one right.
1. Wrong trim size
The mistake: Using 8.5” x 11” (US letter), 6” x 9” for a short novella, or A4 for a novel. Choosing a trim size that doesn’t match genre conventions.
Why it matters: Trim size is the single most immediate physical signal of whether a book is professionally produced. An 8.5” x 11” “novel” looks like a college essay that got bound. Readers hold it and immediately know something is off. Trade fiction is never printed at letter size.
The fix: Use a standard trade trim size that matches your genre:
- 5” x 8” — Compact, common for mass-market-style fiction
- 5.25” x 8” — Slightly wider, popular for romance and genre fiction
- 5.5” x 8.5” — A versatile middle ground, very common in indie publishing
- 6” x 9” — Standard for literary fiction, nonfiction, and longer novels
See the complete trim size guide for genre-specific recommendations.
2. Margins too tight
The mistake: Using the minimum margins allowed by KDP or IngramSpark (often 0.25” on the outside). Cramming text as close to the page edges as possible to reduce page count and printing cost.
Why it matters: Tight margins make a book feel cheap and claustrophobic. The reader’s thumbs cover the text when holding the book. The inner margin (gutter) is too narrow, so text disappears into the spine crease. Professionally typeset books have generous margins that give the text room to breathe.
The fix: Use proper book margins. A good starting point for a 5.5” x 8.5” book:
- Outside margin: 0.625” to 0.75”
- Top margin: 0.75”
- Bottom margin: 0.875” to 1”
- Inside (gutter) margin: 0.75” to 0.875” (wider for thicker books)
The gutter must increase as page count increases. A 400-page book needs a wider gutter than a 200-page book because more paper folds into the spine. See the margins and gutter guide for page-count-specific recommendations, or use the margin calculator to check your values against KDP and IngramSpark minimums for your page count.
3. Times New Roman body text
The mistake: Using Times New Roman as the body font for the entire book.
Why it matters: Times New Roman was designed in 1931 for The Times newspaper. It’s optimized for narrow newspaper columns at small sizes, not for book-length reading on a 5.5”-wide page. It’s the default font in Word, which is exactly why it screams “I formatted this in Word and didn’t think about typography.”
Professionally published books virtually never use Times New Roman. Its absence is expected. Its presence is noticed.
The fix: Choose a proper book font. The best fonts guide covers this in detail, but the short list:
- Garamond — The safest choice. Elegant, readable, professional. Works for everything.
- Caslon — Slightly more personality. Great for literary fiction and romance.
- Baskerville — Clean and refined. Modern feel.
- Palatino — Warm and readable. Good for nonfiction.
Use the book fonts tool to preview fonts at different sizes and pairings.
4. No scene break markers
The mistake: Using only blank lines between scenes, with no visible marker (asterisks, ornament, or rule).
Why it matters: Blank lines vanish at page breaks. When a scene break falls at the top or bottom of a page, the reader has no way to know it happened. One scene ends, the next begins, and the POV or time shift occurs without warning. The reader gets confused and blames your writing, not your formatting.
The fix: Use a visible scene break marker — three centered asterisks (* * *), a small ornament, or a horizontal rule. Your formatting tool should automatically handle the edge case where a scene break falls at a page boundary. Cambric detects scene breaks from your manuscript and renders them with your chosen ornament style, automatically handling the page-boundary edge case so the break is always visible. See the scene break formatting guide for conventions by genre.
5. Missing or ugly chapter openers
The mistake: Starting each chapter with “Chapter 1” in the same font and size as the body text, with no vertical space above it, no drop cap, and no visual distinction from a regular paragraph.
Why it matters: The chapter opener is the most visible formatting element in your book. It’s also the most visible difference between professionally formatted and amateur-formatted books. Every traditionally published novel has a designed chapter opener with a sink (vertical white space), a styled heading, and usually a drop cap. Every.
The fix: Design your chapter openers with:
- A sink (blank space) pushing the heading down at least one-third of the page
- A chapter number in a display size or complementary font
- An optional ornament or rule
- A drop cap on the first paragraph
- A small-caps first line
See the chapter opener design guide and the drop caps guide for detailed instructions.
6. Widows and orphans everywhere
The mistake: Leaving single lines stranded at the top or bottom of pages — a lonely last line of a paragraph at the top of a page (widow) or a single first line at the bottom (orphan).
Why it matters: Widows and orphans are the most common typesetting flaw in self-published books and the most visible to anyone who reads traditionally published books. They look careless. They waste space. They break reading flow.
The fix: Go through your final PDF page by page and check the top and bottom of every page. Adjust paragraph breaks, tracking, or page breaks to eliminate stranded lines. Most professional formatting tools have widow/orphan control settings, but none are fully automatic — manual review is still necessary. The widow and orphan control guide explains the techniques in detail.
7. Wrong page numbering
The mistake: Starting page numbers on the first page of the PDF (the half-title page). Using Arabic numerals (1, 2, 3) in the front matter. Putting page numbers on blank pages, chapter openers, or the copyright page.
Why it matters: Professional books follow a specific page numbering convention. Front matter uses lowercase Roman numerals (i, ii, iii) or no visible numbers at all. Arabic numbering (1, 2, 3) starts at Chapter 1 (or the first page of the body text). Page numbers are suppressed on blank pages, chapter openers, and certain front matter pages. Getting this wrong is an immediate tell.
The fix: Follow the standard convention:
- Front matter: Roman numerals or no visible page numbers
- Body text: Arabic numerals starting at 1 (or continuing from front matter)
- Suppress page numbers on: title page, copyright page, dedication, blank pages, chapter opener pages, part opener pages
See the page numbering guide for the complete convention.
8. Missing front and back matter
The mistake: Starting the book with Chapter 1 on the first page. No title page, no copyright page, no table of contents. Ending with the last chapter and nothing else.
Why it matters: Front and back matter are structural elements that every reader expects. A missing title page looks like a bound manuscript. A missing copyright page looks unprofessional and leaves you legally unprotected. Missing back matter (about the author, also-by page) wastes your biggest marketing opportunity — the moment when a reader has just finished your book and wants more.
The fix: At minimum, include:
Front matter: Half-title page, title page, copyright page, dedication (optional), table of contents (required for nonfiction, optional for fiction)
Back matter: Acknowledgments (optional), about the author, also-by page (essential for series authors), a note asking for reviews (optional)
9. Inconsistent spacing
The mistake: Different amounts of space between paragraphs on different pages. Some paragraphs indented 0.25”, others 0.5”. Line spacing that varies between chapters. Extra space after some headings but not others.
Why it matters: Inconsistency is the enemy of professionalism. Even readers who can’t articulate what’s wrong will feel that the pages don’t look uniform. Inconsistent spacing usually results from manual formatting in Word — adjusting individual paragraphs instead of using styles.
The fix: Use paragraph styles consistently throughout the entire manuscript. Set your first-line indent once (0.3” to 0.5” is standard), your line spacing once (typically 1.15 to 1.35 for print), and your space-after-paragraph once. Apply these styles globally. Never override them on individual paragraphs unless there’s a structural reason (like the first paragraph after a heading, which should have no indent).
The formatting checklist helps you audit your manuscript for spacing inconsistencies.
10. Images not optimized
The mistake: Using low-resolution images (under 200 DPI) that print blurry. Using enormous uncompressed images that inflate file size and cause upload failures. Not accounting for grayscale conversion on black-and-white interiors.
Why it matters: A blurry map on the first page of your fantasy novel, or a pixelated author photo in the back matter, undermines the entire book’s perceived quality. And oversized images can cause KDP or IngramSpark to reject your upload.
The fix: For print interiors, all images should be 300 DPI at their printed size. For black-and-white interiors (standard for novels), convert images to grayscale before placing them. For ebooks, optimize images for screen resolution (150 DPI is sufficient) and compress to keep file sizes reasonable. See the ebook formatting guide for ebook-specific image requirements.
11. No font embedding in PDF
The mistake: Exporting a print-ready PDF without embedding the fonts. The PDF opens fine on your computer (which has the fonts installed) but prints with font substitutions at the printer.
Why it matters: If your fonts aren’t embedded in the PDF, the printer’s system substitutes whatever fonts are available. Your carefully chosen Garamond becomes Courier. Your headings in Source Serif become Arial. KDP and IngramSpark may reject the file outright, or worse, print it with the wrong fonts.
The fix: When exporting to PDF, always embed all fonts. In most tools, this is a checkbox in the export settings:
- Word: File > Options > Save > “Embed fonts in the file”
- InDesign: Export to PDF/X-1a or PDF/X-4 (fonts are embedded by default)
- Dedicated formatting tools: Most embed fonts automatically
After exporting, open the PDF and check the font list (in Acrobat: File > Properties > Fonts) to verify every font is listed as “Embedded” or “Embedded Subset.”
12. Hard returns instead of paragraph styles
The mistake: Using the Enter key to create spacing between paragraphs instead of paragraph styles. Pressing Enter twice between every paragraph to create a visual gap. Using Enter to push text to the next page for chapter breaks.
Why it matters: Hard returns (manual line breaks) create spacing that’s fragile and unpredictable. When the text reflows — because you changed the font, adjusted margins, or imported the file into a formatting tool — those hard returns create uneven gaps, pages with too much white space, and chapter breaks in the middle of pages.
In ebooks, the problem is even worse. Hard returns that looked fine in your Word document create massive blank spaces in a reflowable ebook.
The fix: Use paragraph styles for all spacing. Set “Space After” for paragraphs instead of double-enters. Use page breaks (Insert > Page Break in Word) for chapter breaks instead of hitting Enter until the text pushes to the next page. When you import a clean, styles-based document into a formatting tool, everything flows correctly.
The meta-mistake: formatting by eye
Behind all twelve of these mistakes is a single root cause: formatting by appearance rather than by structure. When you adjust individual paragraphs by eye, you get inconsistency. When you apply styles and structure, you get uniformity.
Every professionally formatted book is built on structure: a consistent set of styles (body text, first paragraph, heading 1, heading 2, scene break) applied uniformly from the first page to the last. The visual appearance flows from the structure, not the other way around. This is the principle behind Cambric’s template-based approach — you work with your manuscript’s structure (chapters, scenes, front matter), and the typesetting engine produces the correct visual output for every page.
The checklist approach
Use the formatting checklist to audit your book against these twelve mistakes before you publish. Go through each item. Check your trim size, check your margins, check your fonts, check your scene breaks, check your chapter openers, check your page numbers, check your front and back matter, and check your widows and orphans.
It takes an hour. It’s the difference between a book that looks like it belongs on a bookstore shelf and one that doesn’t.
Cambric is built to prevent these twelve mistakes by design. Its 20+ professional templates enforce consistent chapter openers, scene breaks, margins, and page numbering across your entire book. The live preview shows you exactly how every page will print — widows, orphans, and all — before you export a print-ready PDF or EPUB. It’s a one-time $109 desktop app that runs locally on your machine. No surprises in the final file, no subscription to maintain.