One of the first things many self-help books do is ask you to write down your goals and write a mission statement. If I could do that, why would I need this book?
Here is one solution to finding out who and what you are: Pretend you're a detective! Look for clues...
I can tell my interests by the books on my shelf: art, culture, science, history, philosophy, metaphysics, cooking, health, business.
I can tell what's important to me by what I strive for: financial security, love, respect, raising my children, spirituality, self improvement.
I can tell what I think of spirituality by my notions of how I suspect things work. (Hardly anybody believes there are no unseen forces in the universe, if you include science as an unseen force.)
I can tell my hobbies by how I want to spend my time: music, conversation, art, nature, exercise, studying, working.
I can tell what qualities I appreciate by looking at my friends: intelligent, talented, interested, trustworthy, philosophical, funny.
I can tell what I might become by looking at my parents. My dad is hard working, strong, impulsive, artistic, practical, critical. I can see that. My mom is a uh... kitten who believes in magic, likes to take care of people, but runs away from trouble. I am a flirt who is confused about her spirituality, wants to take care of people but not sure if she can, and vowed to never run away from trouble (possibly to my detriment). I think I need to understand my mom better.
I can tell what I need to work on by looking at what's a mess: the room I am sitting in right now. : )
Thanks for reading. I hope this approach might come in handy for someone. Whoever you are...