Summarize:

He will often offer you counsel on how you can avoid sin in the future. Afterward, he will ask you to make an Act of Contrition. This must be performed sincerely, truly meaning what you say. If you don't know the words, write them down or ask the priest to help you. At the end of your session, he will probably recommend penance (to be performed as soon as possible). At the end of the absolution he will say, “I absolve you of your sins in the name of the Father, the Son, and the Holy Spirit.”  If he makes the Sign of the Cross, follow suit.  He will then dismiss you, saying something to the effect of “Go in peace to love and serve the Lord.”  Reply, “Thanks be to God,” give the priest a smile, and exit the confessional. Return to the church and assume your prior seat. When you begin your penance, give thanks to God for forgiving you. If you recall some serious sin you forgot to tell, know that it has been forgiven with the others, but be sure to confess it in your next confession. If the priest gave you penance that consists of some prayers to be recited, say them quietly and devoutly. Kneel in the pew, hands clasped and head down, until you have completed your penance and have adequately reflected on your experience. Resolve to return to the Sacrament of Reconciliation often. Rise joyful and confident for the Lord loves you and has been merciful. Live for Him every minute of your life, and let everybody see how wonderful it is serving the Lord. Stay mindful. Don't use confession as a reason to excuse sins. Rejoice that you are forgiven and live as God intended you to to minimize the need for confession.
Listen to the priest. Complete your penance. Leave feeling better and living in the light of God's forgiveness.