RGB is for screens; CMYK is for most print. Files submitted in RGB will be converted, and colors can shift. Building in CMYK from the start gives you more control.
Why colors shift
Monitors emit light in red, green, and blue. Print uses cyan, magenta, yellow, and black ink on paper or vinyl. The same numeric values produce different looks. Bright neon-style colors on screen often cannot be reproduced in CMYK.
Setting up for print
Create your document in CMYK color mode when the output is print. If you start in RGB, convert to CMYK before sending and expect some color shift—especially in saturated blues and oranges.
Before you send the file
• Set document color mode to CMYK (or confirm conversion before export).
• Use swatches or defined CMYK values for brand colors.
• Review a soft proof or printed sample if color is critical.
Common mistake
Designing in RGB and assuming "it will look the same in print." Conversion and substrate will change the result. Plan for CMYK and expect a proof if color must match.