What an awesome question!
In my experience, I wish I knew to trust myself at a younger age. Life is infinitely complicated and curve balls are everywhere. What feels like "stuck" could really just be your inner self telling you to quiet down and listen for your next move, with your heart, not your head. If anything stifles inspiration for me, it's doubt and fear. Try not to fall into the cycle of "I should do this" and "people expect me to do that..." Be you. Above all things, trust that you have something unique to offer the world.
Whenever we feel unsure of our purpose, it's good to check in with our dreams. Literally. What is your dream? If you don't know the answer to that, try asking yourself what your nightmare is- and work backwards. As they say, "If you don't know where you're going, any path will get you there." Get clear on your dream. The rest will evolve naturally.