Nothing loosens up the spirit & gets ideas flowing like singing.
It doesn’t matter whether you can carry a tune, shatter crystal or have a tin ear, singing increases the oxygen in you blood, and gives both hemispheres of the brain a nice workout, plus it’s just plain fun.
So stand up, move around, and belt out a song. Sing loud. Scare the cat, wake up the neighbors. Startle your coworkers in the breakroom. Make your spouse/parents/children wince, or better yet, get them in join in.
Don’t sing along with the radio, though—this is YOUR song.
Style it! Sing in a funny voice: do a jazz standard in a punk style, sing a theme song as an aria, rap a hymn, give a lullaby a Latin beat. Or choreograph some movements; you can even use your hairbrush as a microphone.
Afterwards, notice how great you feel?