The prayer to start with.
If we confess our sins, he is faithful and righteous to forgive us the sins, and to cleanse us from all unrighteousness. 1 John 1:9
As far as the east is from the west, so far has he removed our transgressions from us. Psalm 103:12
Lord, I’ve done wrong, and I’m sorry. I won’t make excuses. Forgive me, and cleanse me. Thank You that You are faithful and just to forgive. Help me not to repeat it. Let me walk away lighter, and closer to You. In Jesus’ name, amen.