I wrote this a while ago but I think it applies
#1 Take a break from the typical genres you enjoy. If you only listen to hip-hop check out metal, if you only like fiction get some non-fiction, if you look at surrealistic paintings….well you get the idea. Spend some time with these new genres, get to know and enjoy them.
#2 Get two magazines, find a page in each magazine with people on them. Rip the page out of each magazine. Now write a short story as to how these two people are connected.
#3 Everyday get out for at least a 20 minute walk by yourself with no phone or music players. You need to be alone with your thoughts.
#4 Go to a new part of town you have never been to before. Go to a new coffee shop and strike up a conversation with a stranger. Maybe someone you would normally be afraid to talk with, it also helps if they have totally different religion and/or political views are you. Try and really see their side and be in their shoes. Make a new friend and get a new perspective.
#5 Take up a new instrument that you would never consider playing. Maybe the bagpipes, the culture around that instrument alone will help get you out of the funk. Victor Wooten for example (one of the best bass players alive) had Bela Fleck teach him some things about the banjo, and Victor took those lessons and applied them to his bass playing, Amazing!