The page was resized
The artwork was fitted to a standard paper size, or the whole sheet was redrawn at a size that looked close. The panels no longer line up with the book, and nothing on the sheet is where the press expects it.
Guides — AI
How to place artwork on a book template with an AI assistant
Most people now hand the template and their artwork to an AI assistant and ask it to combine them. This is the page to give the assistant. It states the rules a template file has to obey, and how to read the job block we embed in every template.
If you are using an assistant
Give it the template, and this page
Attach the template PDF we sent you — the file itself, not a screenshot of it — and paste this:
Follow the instructions at https://www.custombookstudio.com/guides/ai-artwork-setup/ and the job block inside the attached template PDF. Place my artwork on the template without changing the page size, and export with the Template layer hidden.
Attach the PDF, not a picture of it. The template carries the job — page size, trim, bleed and what each panel is — as text inside the file. A screenshot or an exported image throws that away, and the assistant is left measuring a picture and guessing.
The rules
What a template file has to obey
In order. The first two account for most of the files we have to send back.
Step 01
Read the job block inside the template
Every template we issue carries a short block of text naming that job: the exact page size, the trim, the bleed and what each panel is. It is invisible on the page but present in the text, so extract the text before doing anything else and follow the numbers it gives rather than measuring the picture.
Step 02
Never change the page size
The template page is already the finished sheet. Resizing it, scaling it to fit, or exporting to a standard paper size is the single most common way an AI-prepared file arrives wrong. Place artwork INTO the page at its existing size.
Step 03
Put artwork on a new layer beneath "Template"
Our guides live on a PDF layer named Template so they can be switched off. Add your own layer under it. Do not draw on the Template layer, and do not copy our guide marks into the artwork.
Step 04
Fill each panel with the panel that belongs there
A cover or endpaper sheet holds several panels side by side and they are not interchangeable — the job block names them left to right. Repeating one panel across the sheet, or mirroring the wrong half, produces a book with the wrong thing printed inside the cover.
Step 05
Export with the guides gone, not flattened
Hide or delete the Template layer and export. A flattened export bakes our trim and safety marks into the artwork as permanent ink, and they will print on the finished book.
The job block
What is written inside every template
Each template we issue carries a short block naming that specific job. It is set in invisible text — nothing is drawn on the page — so it costs the design nothing and survives being opened in any tool that can read text.
<<<CNTRLP-ARTWORK-BRIEF>>>
INSTRUCTIONS: https://www.custombookstudio.com/guides/ai-artwork-setup/
JOB: Heirloom Family Book
SHEET: front endpaper sheet
PAGE: 23.500 in x 32.050 in - this is the sheet you were given. DO NOT CHANGE IT.
ARTWORK AREA: 20.500 in x 12.500 in - fill this, inside the page above
TRIM: 10.000 in x 12.000 in - the finished book
BLEED: 0.250 in
PANELS: top row: inside front cover, visible | front outside flyleaf. bottom row: front inside flyleaf | paste-down, hidden, glued to the board
RULE: place artwork on a NEW layer BENEATH the layer named Template.
RULE: do not resize or rescale the page. Do not add crop or registration marks.
<<<END-CNTRLP-ARTWORK-BRIEF>>>Take every measurement from that block rather than from the appearance of the page. If the block and the picture disagree, the block is right.
By book type
Find your binding, and ignore the rest
Each binding is a different object with different sheets. Your template links straight to the one that applies — if you arrived here another way, pick it below.
Hardcover
A printed case wrapped around boards, with endpapers pasted inside the covers. It has the most sheets of any binding, and the endpapers are the ones people get wrong.
| Sheet | What it holds |
|---|---|
| Casewrap | back cover | joint | spine | joint | front cover, across one sheet. The bleed here is NOT trimmed off — it wraps the board edge and folds inside the case. |
| Front endpaper | One folded sheet, two panels across, stacked twice on the page. Top row: inside front cover (visible) | front outside flyleaf. Bottom row: front inside flyleaf | the paste-down’s hidden back. |
| Back endpaper | MIRRORED, because the sheet folds the other way at the back of the book. Top row: back outside flyleaf | inside back cover (visible). |
| Dust jacket | Only when the book has one: back flap | back cover | spine | front cover | front flap. |
| Interior | One PDF page per book page, in reading order, every page the same size. |
Softcover — perfect bound
A single cover sheet wrapped around the pages and glued at a flat spine. There are no endpapers: the inside of the cover is the back of the same sheet.
| Sheet | What it holds |
|---|---|
| Cover | back cover | spine | front cover, across one sheet. The spine has a real, measured width — the template states it. |
| Interior | One PDF page per book page, in reading order, every page the same size. |
Saddle-stitched
Folded sheets stapled through the fold. THERE IS NO SPINE — the middle of the cover is a crease, and anything laid out as spine type will be folded down the middle of it.
| Sheet | What it holds |
|---|---|
| Cover | back cover | fold | front cover. Do not put a title, a logo or any deliberate mark across the fold. |
| Interior | One PDF page per book page, in reading order. The page count is always a multiple of four — a folded sheet makes four pages. |
Wire and plastic coil
Covers and pages punched along the binding edge and threaded with wire or coil. The punched strip is destroyed by the holes, so nothing you need to keep may sit in it.
| Sheet | What it holds |
|---|---|
| Covers | Back and front, side by side on one sheet or supplied as single panels. The binding edge of each is PUNCHED — keep artwork out of the punch margin the template marks. |
| Interior | One PDF page per book page, in reading order, with the same punch margin on the binding edge of every page — and that edge alternates, left on one page and right on the next. |
What goes wrong
The four failures we actually see
Not hypothetical. These are the files that arrive and have to be sent back.
The guides were flattened in
The export dropped the layer structure, so our trim and safety marks became permanent ink in the artwork. They will print on the finished book.
One panel was repeated
The same artwork was placed in every panel of the sheet, or the mirrored back sheet was treated like the front. The book comes back with the wrong thing printed inside the cover.
Crop marks were added
The assistant added registration or crop marks because a print file usually has them. Ours does not need them — the sheet is already the finished size — and they print into the job.
If you are not sure which of these has happened, send us the file and we will tell you. Checking a file costs nothing and takes us a few minutes.
Next
The measurements themselves
This page is the method. The numbers a cover and an interior have to hit are in the other two guides.