How to prepare a file for printing

To prepare a file for printing, send a PDF at the exact trim size with 3 mm of bleed on every edge, keep text and logos at least 3 mm inside the trim, use images at 300 DPI at their printed size, supply colour in CMYK or ask the shop to convert it, embed or outline the fonts, and state the paper and finish in the order. Those are the requirements almost every print shop publishes. If your file cannot meet one of them, the fix is to tell the shop before they print, not after.

The table under this article is a checklist of what shops ask for, what a flyer exported from this builder contains, and what to do about the difference.

Size and resolution

Start with the finished size, which printers call the trim size. An A4 flyer trims to 210 by 297 mm, an A5 to 148 by 210 mm and a DL to 99 by 210 mm. Write the trim size in the order even when the file seems obvious, because it is the number the guillotine is set to.

Then check resolution. CBS Printing, an Australian commercial printer, asks for photographs and illustrations at 300 DPI, and PrintingForLess recommends the same figure. That means 300 DPI at the printed size: an A4 page at 300 DPI is 2480 by 3508 pixels. A photograph dropped into a slot and stretched larger than its pixels allow will print soft whatever the file’s overall resolution says. The flyer sizes guide lists pixel dimensions for every common size, and what DPI a flyer needs explains when less is enough.

Bleed, trim and safe area

Bleed is artwork that continues past the trim line so a slightly shifted cut still leaves colour to the edge. Paperlust’s print checklist explains the reason: sheets are stacked and cut together, and even a 1 to 2 mm shift changes where the blade meets the paper. Its standard for small format print in Australia is 3 mm of bleed on each edge, with 5 mm typical for large format above A2, and CBS Printing asks for 5 mm on booklets.

Inside the trim sits the safe area. Both guides ask for text, logos and anything that must be seen to sit at least 3 mm inside the trim, and Paperlust suggests 5 mm where a design has weight near its edges. For an A5 flyer that means a canvas of 154 by 216 mm including bleed, with all important content inside 142 by 204 mm.

Bleed only matters when colour or an image reaches the edge. A design with a white margin all round has nothing to bleed, which is one reason plain margins are the most forgiving layout for print.

Colour: RGB, CMYK and black

Presses print in cyan, magenta, yellow and black, and most shops ask for files in CMYK. CBS Printing’s guidelines say all colours should be converted to CMYK unless printing in spot colours, with no RGB. Converting yourself shows you the shift before the press does; letting the shop convert with its own profile is the common alternative.

The colours that move most are the ones screens do best: saturated blues, greens and oranges. If a brand colour matters, ask for a printed proof.

Large areas of solid black are a special case. CBS Printing recommends a rich black mix, black plus some of the other inks, for a deep solid result on large black areas, because black ink alone can print grey and patchy.

Fonts, pages and the PDF itself

Fonts must travel with the file, either embedded in the PDF or converted to outlines, so the shop’s computer does not substitute a different typeface. Pages go in order as single pages, not spreads: CBS Printing asks for a sixteen page booklet as one PDF with sixteen pages, and imposes it for press itself.

For shops that work to industry standards, the Ghent Workgroup publishes best practice specifications for print ready PDFs, including the PDF/X workflow many presses use. You do not need to read them to order flyers, but if a shop asks for a PDF/X file, that is where the requirement comes from.

A worked example: the conference flyer

The conference flyer is three designs for a fictional events company, each on A4. Its forum design has a dark header across the top carrying the event name, then a white lower half with separate blocks for the date, the venue and the audience, and a web address at the foot.

Before sending it to print, run the checklist. The dark header is the part to watch: if its colour runs to the top edge, the file needs bleed there, or the shop needs to know so it can scale the artwork slightly. The date, venue and early bird price sit in the white half, well inside the edges, so a small scale up would not endanger them. The type is large and the design has no small photographs, so resolution is not a risk.

Contrast that with the sale flyer, whose photo led design opens with a large photograph of a made bed. If a photograph like that runs to the edge, bleed and the shop’s handling of it deserve a phone call before the order. The workshop flyer suggests a different case: its three designs are separate A4 sheets, and if you build a set like that as pages of one flyer and export a single PDF, check that the pages are in the order you want them printed and that every page is the same size.

Check the PDF before you send it

Open the exported PDF, not the design, and check it the way the shop will.

1. Page size. Look at the document properties in your PDF viewer, or run it through a PDF page size checker, and confirm every page is the size you expect.
2. Page count and order. Front first, back second, and no stray blank page at the end.
3. Edges. Zoom to each edge and confirm nothing important sits within about 5 mm of it.
4. Photographs at 100 percent. Any image that looks soft on screen at full size will look soft on paper.
5. Spelling and numbers. The date, the price, the phone number and the web address, read aloud once.

This takes five minutes and catches the problems that otherwise come back as a reprint.

Common mistakes

• Text within a few millimetres of the edge, which gets trimmed.
• Background colour stopping at the trim line, which leaves a white sliver.
• Low resolution images enlarged in the layout.
• Sending spreads instead of single pages.
• Not stating the trim size, so the shop has to guess.
• Approving a job without a proof when colour matters.

Build it

A flyer’s PDF export captures every page at twice the canvas size, so an A4 page leaves at 2480 by 3508 pixels, 300 DPI at A4. Each page is placed in the PDF as an image, so there are no fonts to embed and the type prints exactly as it looked. The export has no bleed, no crop marks and no CMYK conversion; it is an RGB file at the flyer’s exact page size. That means three things for a print shop: state the trim size, ask them to convert to CMYK with their profile, and ask how they want to handle bleed. The flyer to PDF page sets out those limits in full.

For a double sided or multi page flyer, add a page from the template library or a blank A4 page, duplicate or delete pages, and export the set as one PDF; the guide to making a multi page flyer shows the steps.