Motivation wall — Put post-its on a wall in your room and share motivation with your roommate or write fun stuff for guests to read when they visit. Have a stack of post-its handy for people to write their own.
My sticky note encouragement wall with bible verses and sayings to keep me going when I get down (LOVE this idea. I had post-its with inspiring quotes/poems on my closet door when I was in high school - A)
You don't need to dedicate so much time to making a complicated motivation board to keep yourself motivated if you don't want to. Just leaving yourself little sticky note reminders and motivational quotes around the house works wonderfully too!