RGB (red, green and blue) is used for digital media and CMYK (cyan, magenta, yellow and black) is for anything printed. RGB is called an “additive color,” meaning the more light emitted the lighter the colors will be. CMYK is “subtractive” which means the more light that’s absorbed, the darker the colors. Computer screens and televisions emit light and ink (for printed material) absorbs light. (Ink doesn’t emit light). So RGB colors on a computer screen will behave, and look, differently when printed on paper.
Remember to include a bleed. And add guides – crop marks – to show the trim area. When a document has an image that touches the edge of the page, the bleed is the part of the image that extends beyond the trim edge. Then when the document is trimmed, there won’t be a white margin.
Crop marks must be printed in the corners of the paper in order for the printer to know where to trim.
Rasterize type. Test must be rasterized in Photoshop or converted to “outlines” in Illustrator, so there won’t be any problems with missing fonts when it’s sent to the printer. If working in InDesign, you don’t need to do either of these if you “package” your file before sending.
Name layers clearly if using spot colors and UV varnish/coating.
Varnishes are transparent so they can be hard to preview on a screen. And when previewing the varnish separation by itself, the varnish areas appear black. Because of the difficulty viewing, it’s important to clearly name the layers for the printing company.
Link files and provide a folder with linked files to the printer.
When exporting a document, InDesign will use the “linked” images to give the necessary information for creating high quality printing. When the link is broken (moved from one folder to another) the information is lost and the printed image will appear blurry.
All of these tips will help prepare your document for the printing process. Any further questions can be asked by a professional design team or your printing company.