One of the high points of the Spiritual Exercises of St. Ignatius is the general confession. Let me point out that this is not the same as general absolution. If you have never done a general confession before, I would highly recommend it. It doesn't have to be done on a retreat, but it should be done with a lot of prayer.
The Miles Christi priests take the first day of the silent retreat to prepare you for this confession. You do several meditations on the Passion and suffering of Christ so that you can attain true sorrow for all of the sins that you have committed throughout your life. During this process, you spend your free time praying that God will reveal to you the sins of your life that you need to confess. The best way to go about this is to start at the youngest age you can remember. Think about where you lived and the people who were in your life at the time. Ask God to reveal to you the sins you need to confess from that time period. Then, when you feel you have exhausted that time, move to another logical block of time. For example, your first time frame could be from your earliest memory through grade school, then you can focus on high school, then college age years, etc. Be prepared to encounter some pretty tough things at this point.
It takes awhile to go through this whole process, but you would be amazed at the things that pop back into your mind. Even sins you thought you had confessed might come up again, so it is okay to include those in this general confession. Make sure you have enough paper to write it all down, too! Once you have gone through your life up to the present day, schedule your confession and tell the priest that this will be a general confession so that he will be prepared.
The truly amazing part happens next. When you walk out of that confessional, you literally feel as if you dropped 10 lbs. The satisfaction you get in ripping up your paper into very tiny little pieces is incredible. The penance you have to perform is a beautiful experience. Again, if you have never done anything like this and you feel like you are carrying around a lot of baggage, find a good priest to guide you and try it out. You will be amazed at the graces that flow through this sacrament. Better yet, sign up for the next retreat!!
God Bless!