It is important to know that we are not saved by our works, but by faith in Christ Jesus and the work that He did for us: Titus 3:5, "Not by works of righteousness which we have done, but according to his mercy he saved us, by the washing of regeneration, and renewing of the Holy Ghost."
Our sins are paid for by the Blood of Jesus and nothing less will do: Matthew 26:28, "For this is my blood of the new testament, which is shed for many for the remission of sins." Do not try to 'earn' your salvation or forgiveness of sins... you must realize that it is by faith in Christ that saves you, not your works! Good works should follow naturally as you grow in your relationship with God (after all, we will become more like Him as we grow spiritually), but that by no means will justify you of past sins.