Be a better caterpillar or become a butterfly.
OK, so women will get this but guys...I know this doesn't sound very manly but suspend your reality for a moment to get the metaphor. What does one do to be transformed, not into a better caterpillar but into a new creation, a butterfly? God calls us to be not re-newed creations but "new" creations.
The main thing that we as Christians must do after saying "Yes" to Christ is to change our thinking [the Greek word for repentance is not turn 180 degrees like most teach but it is "metanoia" which means to think again]. We must change our thinking. We must think not about learning/understanding/applying more but about getting a suntan. If we spend time in the sun we will get tanned. Our "work" consists not of doing anything about our tan but about our position. We can't learn enough about Christ to become transformed and we can't apply or ply enough understanding into our lives to enact change. What we can and must do is put ourselves in the sun. We must spend time doing what we were made to do which is worship and serving others. If we do those things then transformation happens, not because we are making it happen but because our position with God allows it to happen. God operates on us when we put ourselves in His environment. When we set ourselves up as the arbiter of our lives and control it then God cannot work. He has bound His power by giving us free will. We can choose to ignore Him. We can choose to live lives outside His will. We can choose, as Christians, to live lives that are "right" but have no relationship to what He is doing and that leave our lives lackluster and shallow and broken....and un-transformed.
I know many Christians who live pretty exemplary lives doing the do of church attendance and are pretty happy and content with life but whose lives do not exhibit Christ. I worry about them. More perhaps than I worry about non-believers. At least I know, and non-believers know, where they are. It is this muddled group that rocks my boat. They have been Christians for years and yet seem to live lives no different than the life of a non-believer. No greater comfort or solace. No better relationships. Same divorce rate. Same pornography usage rate. They suffer the same devastation and frustration and despair during trials.
I also know a few Christians who are in love with Jesus and for whom the tossing of the world seems to have no impact. They do not seem pressured to perform. They play well. They serve easily and have open hands to others. They engage often in church activities but are not hyper-religious or self-righteous or proud. They forgive easily and are pliant with others. They lead if pressed into service but follow well even in leadership with a servant heart. "How can I be Christ to you?" seems to be the lens through which they look at every encounter. Not Christ the teacher or lecturer or judge but Christ at the well, Christ with the adulterous woman, Christ washing feet.
After "Yes"? Worship and serve. Those will compel you to learn and understand more about this God we adore. Metamorphosis happens in His presence, better caterpillars are made the other way around.