Contrition, to be sincere, must include what the Catechism calls "firm resolution". But even with such intent, there is no certainty that I will not sin in the future and will need repeated access to the Sacrament of Penance and Reconciliation. That would be presumptuous as we are sinners until our last breath.
Firm resolution includes action and a sincere desire to not fall back into sin after confession. There are actions that indicate firm resolution:
1. As soon as possible repair the faults that can be repaired. This includes asking forgiveness from those one has injured and rectifying, at the first opportunity, rash judgment and slander, returning what was stolen, etc.
2. Eliminate the opportunities which can drag us into new sins, such as severing or modifying relationships, avoiding idleness or sleepy mornings, changing a particular walking route; giving up types of media, reading, entertainment or conversation, etc.
So what? Each new sin requires a new confession and a new absolution. God never tires of forgiving.
One asks "If I always commit the same sins, is it because I am not making progress and therefore my confessions are ineffective"? We can believe we are not progressing in the spiritual life but if the attachment to sin decreases, and our relapses make us more humble and wary, we are improving in the realm of the spirit.
Contrition is sorrow for having offended God. This sorrow is not necessarily accompanied by tears or even a deeply felt sadness. The sorrow includes the desire, perhaps imperfect, not to relapse again. If you are willing to do what is in your power to avoid the chances of relapse you have sufficient contrition. The grace of the sacrament will do the rest.
Very often we lack contrition because our examinations of conscience are superficial and our confessions are mechanical. If we took more time to examine our conscience and understood better what God expected of us by reading the Gospel and the lives of the saints; if our prayers were more intense and serious, we would have more contrition.
Additionally, contrition is a gift from God. Like all spiritual gifts, it is obtained through prayer. One might complain about not having real contrition but have we asked God for it?
There are people who cannot leave their homes without repeatedly checking that they have remembered to turn off the stove.
So there are also people who, once their confession has been completed and absolution granted, would like to return to add details. When they leave the confessional they may remember a forgotten sin and the worrying begins. They ask "Will I be able to take Communion tomorrow with this sin on my conscience"?
Neither confession nor absolution are material acts. Undoubtedly, one must confess grave sin. But contrition is a disposition concerning all our sins and shortcomings, even those ignored by us. I have sorrow that I have offended God because I love him. Love is comprehensive; we don't love someone partially, we love them totally and we hate everything that upsets them. Likewise, absolution frees us from all our sins to the extent of our contrition and not only to the comprehensiveness of our confession.
At the next confession, if you remember a forgotten sin, tell the priest. Be consoled by the priest's words at the end of confession: "Go in peace". Certainly the sacrament was instituted to comfort souls not torment them.
The saints went to confession often and considered themselves the greatest of sinners. This was not from false piety but from great love for God. Love is delicate and demanding.
If you have "nothing to say" it may be because you are examining yourself too quickly or superficially. Have you ever read a thorough self-examination and seriously applied it to your real life? Such a process considers not only one's most outrageous sins, but also one's intentions and thoughts buried deep in the heart.
There is a great deal to consider and say in the confessional! For instance, if you have never killed another person, have you ever had hatred, jealousy or envy toward your neighbour? Have you ever wronged him, or wanted to hurt him? Perhaps you have never stolen but do you love money too much? You may not have committed adultery but is your heart really chaste? Are you sure that you love your neighbour? If you have not criticized anyone maybe you did not render all the services that your neighbour could expect of you?
Most examinations of conscience follow a format. There is a review of God's commandments, the commandments of the Church and a review of the seven deadly sins. However, this system has limitations and shortcomings. There is a risk of forgetting the essential virtue of charity and the duties of one's state of life.
A much simpler review considers duties toward God, neighbour and oneself.
Finally, a more complete review would consider our failures in the theological virtues of faith, hope and charity and the cardinal virtues of prudence, justice, fortitude and temperance.
Whatever approach is adopted, never forget to ask yourself a few essential points: Have I deepened and developed my faith? Have I prayed, not only in the morning and in the evening, but in temptation, trial and joy? Have I offered service to a neighbour in need? Have I been too attached to money? Have I conscientiously paid my staff? Have I been conscientious in my professional duties, toward my family and my social responsibilities? Have I forgiven those who wronged me? Did I correct the wrongs I did? A question to consider, rather than focusing on whether I was late for Mass, is whether those around me are happy or unhappy through a fault of mine. Am I a sower of peace and joy?
Read the Sermon on the Mount and the Beatitudes. For a good confession, ask yourself whether what you do, desire, think and who you are conforms to this ideal of Christian life.