Use the past! 

Use the forms others have forged.  Like the way Beethoven did that key change?  Try it—see if it works for you.  Think Virginia Woolf had a great structure for Mrs Dalloway?  Mimic it: that's what Michael Cunningham did for The Hours.

Write a sonnet.  A sestina.  Copy a favorite artist's painting strategy.  Write new lyrics to "Hey, Jude," then write new music for your lyrics.

Recreate a beautiful garden photo in your back yard.

Start with a classic cocktail — change one of the ingredients.  Presto!  A new drink!

"Good artists borrow; great artists steal."

You can read blog posts about STEAL FROM THE BEST here.