It all starts with God... here is some excerpt from the book Purpose Driven Life by Rick Warren.
What do I want to be? What should I do with m life? What are my goals, my ambitions, my dreams for my future? But focusing on ourselves will never reveal our life's purpose. The Bible says, "It is God who directs the lives of His ceatures, everyone's life is in His power."
In other words, we must begin with God. Int is only in God that we discover our origin, our identity, our meaning, our purpose, our significance, and our destiny.
The only way we can find out our meaning and purpose in life is revelation. That is .. ask God. God has not left us in the dark to find out our purposes in life. He has clearly revealed His purposes in our lives through the BIBLE.
We must turn to God's word, not the world's wisdom.