This is called “sanctification“.
He uses all of life including trials and tribulations to strengthen Christ-like traits in us. Just like physical exercise makes our body suffer in order you strengthen us, trials are spiritual exercises that strengthen Christ-like traits in us so that we will be more like Christ. The Christ-like traits He’s trying to grow in us are the fruit of the Spirit: love, joy, peace, forbearance, kindness, goodness, faithfulness, gentleness and self-control. (Gal 5:22-23)
The first step to be like Christ is, of course, to put your faith in him. That’s justification.
When we die, those who are justified will be fully made clean and live in direct fellowship with God. That’s glorification.
In between justification and glorification is sanctification – which is the process to make you more like Christ.