This seems like it might be fun to try.
(found on SkyLandWarrior (https://www.deviantart.com/skylandwarrior)'s page)
30 Day OC Challenge
DAY 1: Introduction (small doodle with name, age, etc)
DAY 2: Cosplaying as one of you fave characters
DAY 3: fanservice
DAY 4: Chibified
DAY 5: in a different style
DAY 6: With a weapon of choice
DAY 7: 15 minute sketch
DAY 8: Sleeping
DAY 9: in their underwear
DAY 10: In casual/street clothing
DAY 11: Surpirsed
DAY 12: Happy
DAY 13: Sad
DAY 14: As an animal (if they're an animal as human)
DAY 15: Swim wear
DAY 16: Dressed in another one of you OC outfit
DAY 17: Playing video game
DAY 18: As a child
DAY 19: In school uniform