Secret to finding purpose number one - you where created.
"Delight yourself in The Lord and he will give you the desires of your heart." Psalm 37:4
This may seem like a basic fact to most who believe in God, but it is a factor missed when looking for what you should be aiming for. If you where created, then you are not a surprise to God. He's not going to say "hey there, I am shocked you like motorbikes, what a surprise, don't do that!" The desires of your heart from youth that you can identify, before the cynical bitterness of adulthood, and negative comments set in, is your starting point.
"For you created my inmost being; you knit me together in my mother's womb. I praise you because I am fearfully and wonderfully made." Psalm 139:13,14a
Secret to finding purpose number two - free your mind.
"It is for freedom that Christ has set us free. Stand firm then, and do not let yourselves be burdened again by a yoke if slavery." Galatians 5:1
Sometimes what God wants to do with our lives is not within what you have been told is acceptable from a Christian point of view. For example a friend of mine wanted to dance, she was looked down upon by the church she attended. Another friend was upset that some brethren where skipping church to attend the local markets, and set up their own stall, until she heard the testimonies that were starting to come out of it.
God may be saying this to you;
"See, I am doing a new thing! Now it springs up; do you not perceive it?" Isaiah 43:19a
Secret to finding purpose number three - prepare to change.
If you think sitting in the same church in the same superb for your whole life is how you will fulfil your destiny then you will miss it.
Why do you attend the church you attend? Did you ever ask God where you should go? Or did you just go their because it was around the corner. I have to confess I have gone to church just because I wanted to go to a service while on holidays, but I promise you there where no divine appointments there. No prophetic revelations or God encounters beyond the normal experience of church.
Other that than I have always sort God on where to fellowship. Some amazing things have happened too. It is just how I have been since my big God encounter, and was surprised to find not all are like that. God lead me to this full on charismatic church when my husband was still very conservative and I protested. I said "lord he will never come here!" Not only did he attend there, but he was filled with the spirit, spoke in tongues and healed there. God knows best!
You have to be prepared to move. Maybe a different church, maybe a different superb, maybe a different state or country. Abraham moved around, Moses moved around, Jesus moved around.
You might think that niggle is the devil pulling you away, when it could be God calling you forward...