I don't think finding a mentor is a must. We all are unique creatures with so much diversity within us. We can have people who guide us, help shape certain areas of our lives and none of them would be able to really see the full potential we have inside us. Trust yourself and your inner gut - it it much more powerful than all of the mentors in the world combined. And also be active, experiment all the time, try new things - that is my humble advice to entrepreneurs.