Before celebrating the Sacrament of Penance, one should prepare themselves with an examination of conscience. An examination of conscience is a “prayerful self-reflection on our words and deeds in the light of the Gospel to determine how we may have sinned against God” (— Glossary, The Catechism of the Catholic Church.
There are various types of examinations of conscience but regardless of which one you use to prepare yourself for the Sacrament it should be rooted in Scripture; particularly, the Ten Commandments and Beatitudes.
The penitent goes to the confessional to confess his sins to a Catholic priest. The penitent says: “In the name of the Father and of the Son and of the Holy Spirit. Bless me Father for I have sinned. It’s been (length of time) since my last confession. My sins are...”
Then, the priest gives words of encouragement. The penitent might have a question to the priest.
The priest gives the penitent a penance. Then he says: “Say the act of contrition.”
O my God, I am heartily sorry for having offended you, and I detest all my sins, because I dread the loss of heaven and the pains of hell; but most of all because they offend you, my God, who are all good and deserving of all my love. I firmly resolve, with the help of your grace, to confess my sins, to do penance, and to amend my life. Amen.
“God the Father of mercies, through the death and the resurrection of His Son has reconciled the world to himself and sent the Holy Spirit among us for the forgiveness of sins. Through the ministry of the Church may God grant you pardon and peace. And I absolve you from your sins in the name of the Father and of the Son and of the Holy Spirit.”
The penitent leaves the confessional.
Sin is before all else an offense against God, a rupture of communion with him. At the same time it damages communion with the Church. For this reason conversion entails both God’s forgiveness and reconciliation with the Church.” (CCC 1440).
To make a good confession, we need to go through the following:
1- Examination of Conscience
2- Contrition: Contrition is sorrow of the soul and detestation for the sin committed, together with the resolution not to sin again.
3- Confession: Confession to a Catholic priest is an essential part of the sacrament of Reconciliation.
4- Absolution: The priest gives the Absolution: “God the Father of mercy, through the death and resurrection of His Son has reconciled the world to himself and sent the Holy Spirit among us for the forgiveness of sins. Through the ministry of the Church may God grant you pardon and peace. And I absolve you from your sins in the name of the Father
and of the Son and of the Holy Spirit.”
5- Penance: It consists of prayer, an offering, works of mercy, service of neighbor, voluntary self-denial, sacrifices, and above all the patient acceptance of the cross we must bear.