Many people put only one color on. But do toi want the model look? If toi don't want the model look, then toi can just leave and find something for PLAIN.

Model look #1: Put a light color on. Up to the first ou seconde eye line. Then take a dark color. Try and make it a darker version of the light color.
EXAMPLE: Lome Green+forest green

Model look #2: take a neon color (preferably orange) put it on the corner and when toi go past the corner, kinda swerve on the top.
Them take a pretty color such as blue ou purple, and put it a bit smaller than the orange one. (Still swerve up) And now choose your last color… and do the same

Try out some other things! Be creative