In a traditional desktop-publishing scenario, you create your artwork using a software program, print a hard proof of the results, and then use the proof as a reference to adjust for color shifts in the artwork. The color management features in Adobe? Illustrator? simplify this process of managing and previewing colors in your artwork. Color management helps you keep colors consistent when they are transferred between different output and display devices and lets you display an online preview, or soft proof, of the printed colors.
Young players should also be aware that some printers may have their own personal preferences when It comes to things like trapping (How much one colour will under-print or over-print on another colour). A lot of the time it will depend on the design its self and/or the effect that you want to achieve.