In my experience of over 30 years as a graphics designer, I have seen enough bad work by so-called professional as well as amateurs to prompt me to write this blog.
Most of the bad work has come from people who do not know the complete process for creating a document that not only is attractive and functional, but is also suitable for printing.
One of the most popular programs is Adobe® Photoshop. However, this is a raster (pixel-based) program that is the most suitable for editing photographs. Many new features have been added over the years to include text. However, there are much better options available in other page-layout programs such as Adobe® Illustrator, Adobe®InDesign, and CorelDraw®. These are vector-based programs in which the objects and text are shapes rather than clusters of pixels. As such, they are resolution independent. They are also extremely suitable for creating multi-page documents.
Regardless of the software used, there are several key requirements for printing that are often ignored.
Fonts are a major issue because they do not “travel” well. Should a commercial printer not have your font, the job will not be printed correctly. The established procedure for avoiding this is for the designer to convert the text to outlines.
If there are bleeds on a page, images must extend a specific distance beyond the physical end of the page. To assure that the page will be trimmed properly, crop marks are advised.
As for color, designers must know about how colors are printed. Most color printing today is four-color process(CMYK). Thus photos that use the RGB color mode, common to digital photography, must converted to CMYK mode for printing. The document that is submitted for printing should also contain register marks and color bars. For spot color jobs, the file must be suitable for creating color separations.
Complete explanations of some of the terms and processes in this blog were avoided intentionally. If there was something you did not understand, then you are not qualified to design for print.