When it comes to printing your design files, what you see on screen is oftentimes not what you get from the printer. One way to ensure that what you see on your screen will match what comes out of the printer is to check the existing color mode of your design.
Computer screens and digital cameras view color and light in different spectrums than printers do, and failing to sync the two will reflect horribly in your print. Electronics that produce visual light or interpret it via a sensor use the RGB spectrum to make colors, because mixing light in these colors is easy and smooth.
Most (if not all) design software programs use the RGB color mode by default. Printers, however, use the CMYK process to overlay different intensities of each tone and create the full range of colors. This additive process—as opposed to the subtractive RGB system—involves adding color to create deeper colors on the way to black, not adding light to move away from black.
The basic takeaway: if your computer and printer aren’t speaking the same color language, your results aren’t going to come out right. So set your program to CMYK.