The biggest move is to stop thinking about going to confession and just go to confession. Find a parish, find the time reconciliation is offered, and go. The priest will be willing to walk you through the ritual, and there will be prompts there as well.
But if it has been a while and you would feel more comfortable knowing how it is going to go, here is what you will do:
You will likely get in a line for confession. When the person ahead of you confessing leaves the confessional, you can walk in. If there is no line, most confessional rooms have a light on that indicates a priest is waiting to hear confessions. (This explains the name of the website!)
Once you enter the confessional, kneel behind a screen or curtain…or sit in front of the priest for a face to face confession. Usually both options are available and the choice is entirely yours.
Make the Sign of the Cross; and say: “Bless me, Father, for I have sinned. It has been _____ (list the time — weeks/months/years) since my last confession.” An estimate of time is fine.
State your sins honestly and freely. Make sure to name any mortal sins and number of times you’ve committed them. If you are not sure whether something is a mortal sin, you could ask. But just name all the sins you can remember. Remember, the point is that you are admitting your guilt to God through the ministry of the priest, and seeking your heavenly Father’s forgiveness, which He gives so generously and freely when we ask Him.
When you have named all of your sins, end the confession by saying something like, “for these and all of my sins, I am sincerely sorry.”
The priest will offer you words of counsel; listen with an open mind and heart. Then he will assign you a penance (a prayer or an act to make reparation for your sins).
The priest will then ask you to make an act of contrition, which is a prayer of sorrow for your sin. A common act of contrition is as follows: “My God, I am sorry for my sins with all my heart. In choosing to do wrong and failing to do good, I have sinned against you whom I should love above all things. I firmly intend, with your help, to do my penance, to sin no more, and to avoid whatever leads me to sin. Amen.” Often this prayer is available in the confessional. You could use your own words of sorrow to God if you wish.
Listen attentively as the priest prays the prayer of absolution and close with the Sign of the Cross.
Leave and do your penance. It is good to thank the Lord for his mercy before leaving the church.
Afterward, rejoice! Being reconciled to God and his church is something to celebrate! Share your peace and joy with someone else that day.