RECONCILIATION
Those who approach the sacrament of Penance obtain pardon from God’s mercy for the offense committed against him, and are, at the same time, reconciled with the Church which they have wounded by their sins and which by charity, by example, and by prayer labors for their conversion.
–Catechism of the Catholic Church, #1422
EXAMINATION OF CONSCIENCE
It is recommended that you spend some time in prayer before going to confession. As you pray, ask the Holy Spirit to reveal to you your sins. This is referred to as an examination of conscience.
St. John the Evangelist 