Christ gave us this sacrament so that we could hear, with our own ears, that we are forgiven.
Most people who stay away do not stay away because they disagree with the Church. They stay away because they are afraid, or because they don't remember what to say.
You may feel as though your sins are uniquely terrible or embarrassing. They aren't. Priests hear people confess the same kinds of sins over and over again.
More importantly, the priest is there precisely for this: to help you return to God.
You don't need to impress him. You don't need to explain everything perfectly. You just need to tell the truth.
The Church teaches that the seal of confession is absolute. A priest may never, for any reason, reveal what he hears in the confessional.
Whatever you say stays there.
If you have forgotten how this works, say so. "Father, it has been a long time and I don't remember what to do" is a perfectly good way to begin, and he will help you through it.
Priests are genuinely glad when someone comes back after years away.
Take a few quiet minutes to look back over your life since your last confession. This is called an examination of conscience.
You are not building a case against yourself. You are asking God to help you see honestly, and asking for the grace to be sorry for what you find.
The questions below may help. Tap the ones that are true, and at the end it will give you a card: the words to open with, your own list in the middle, and an act of contrition. You can take it in with you.
Nothing you tap is saved anywhere. Not on a server, and not on this phone. It lives in the page while you are here and disappears when you close it.
These questions are a help, not a complete list. If something comes to mind that is not here, bring that too. And if you read the whole list and find little, that is a real answer; you do not have to manufacture sins.
Here is the whole thing, in order.
Most churches offer a screen you can kneel behind or a chair where you sit face to face. Either is fine. The choice is yours.
Make the Sign of the Cross and say:
"Bless me, Father, for I have sinned. It has been [a month / two years / a very long time] since my last confession."
Say them simply. You do not need to explain the circumstances or justify anything. "I lied to my parents." "I have been using people." "I have not spoken to my brother in two years, and that is my fault."
The Church asks that you confess serious sins by kind and, as best you can remember, by number. Smaller sins are worth bringing too, though they are not the reason the sacrament exists.
When you have said everything:
"I am sorry for these and all my sins."
He will usually say something to help you, then give you a penance: a few prayers, or something to do. Listen for it. If you do not catch it, just ask him to repeat it.
He will ask you to express your sorrow. Any of the forms below will do, and your own words are fine. If you cannot remember one, tell him and he will lead you.
He extends his hand and prays the words of absolution, ending "I absolve you from your sins, in the name of the Father, and of the Son, and of the Holy Spirit."
You answer:
"Amen."
At that moment your sins are forgiven. Not probably. Not if you feel it. They are forgiven, because Christ forgives them through the priest.
He will send you out, often with "Go in peace." Then find a pew and do what he asked. The whole thing usually takes only a few minutes.
What matters is that you are truly sorry and intend, with God's help, to turn away from sin. The words are how you say that.
O my God, I am heartily sorry for having offended thee, and I detest all my sins because of thy just punishments, but most of all because they offend thee, my God, who art all good and deserving of all my love. I firmly resolve, with the help of thy grace, to sin no more and to avoid the near occasion of sin. Amen.
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 penance, to sin no more, and to avoid whatever leads me to sin. Amen.
Parishes often print one of these on a card in the confessional. If you would rather use your own words, tell God you are sorry and that you mean to try again with His help. That is an act of contrition.
If you forgot it honestly, it is forgiven with the rest. Mention it next time if it stays on your mind. Confession is not a form that gets voided by an omission.
You are welcome to go to a different parish, and many people do. But being known has never once made a priest think less of someone in that chair.
You might. That is not a reason to stay away.
What God asks is that you are sorry now and that you intend to try. Everyone who has taken this seriously has confessed the same sin more than once. Coming back is not failure; staying away is.
Then say that when you sit down, and let him help you. There is no amount of time that makes you unwelcome.
The Church asks that we confess serious sin before receiving Communion, and that every Catholic go at least once a year if they are conscious of grave sin.
Beyond that, many people find that going about once a month keeps them honest and makes the whole thing less daunting. That is a common recommendation rather than a rule, and it is what I would suggest if you are beginning again.
Most parishes hear confessions on Saturday afternoon. To find times near you, wherever you are, use masstimes.org; it lists confession times alongside Mass times.
You can also call the parish office and ask for an appointment. For a first time back after years away, that is often easier: no queue behind you, and as long as you need.
Do your penance before you leave, while you still remember it.
Then let it be over. Going back over it afterward, wondering whether you said it properly, is a way of taking back what you just handed to God.
He has forgiven you. That is the whole point of the sacrament.
There is no one so bad that he cannot become good. There is no one so lost that he cannot be found. Attributed to St. John Bosco