I don't know about you, but the more I think of sin as a concept, of past sins, unconfessed sins, theoretical sins, etc., the more I want to sin. I'm even taking a risk by writing about sin. Even when you do sin it is better to confess your sin to God and then quickly move on. Why cry over spilt milk, as it were? Why frown about the vase that broke and cannot be repaired? Pick up the broken pieces, throw them out and then move on with your day, and with your life. Of course, I am not saying there is no such thing as sin. It would be nice if that were the case. It is obvious that there is something wrong in one's behavior from time to time. However, it is not healthy to dwell on the imperfections of sin.
Do more than just put it out of your mind. If anyone starts talking about Sin or sinning just excuse yourself and remove yourself at once from their presence. That is unless they have asked you to help them because they are weighed down by the burden of sin. You would be sinning again if you were so unconcerned about a fellow human being who is asking you for help.
There are so many worthwhile and useful things you could be doing with your life than dwelling on your sins, past or future. It is better to focus on a more loving version of yourself, a more grateful one, a more ideal one which will, hopefully, bring you closer to that reality.
Even better yet is to focus on Christ, his words, other ideal realities and these exalted realities may very well become your own reality, as well.
What to do with Sin? Leave it alone, in both word and deed. Take a breath of fresh, sinless air, and start enjoying your life today.