One trick to finding your purpose is to think about what you were into as a child.

 
What lit you up, what got you excited, what made you come alive when you were a kid? Try to figure out how to reconnect with the things that have really resonated with you in the past.
Because, oftentimes, we get so caught up in our minds and what we think that we should be doing, that we lose track of our hearts and what our souls really need for us to be doing.