A preacher said,"Jesus paid a debt He did not owe, because we owed a debt we could not pay." Our sins had to be paid for with Jesus' blood. There is nothing that we can offer God to pay for our own salvation. As the hymn goes,"Jesus paid it all. All to Him I owe. Sin had left a crimson stain. He washed it white as snow."
When Jesus was hanging on the cross being sacrificed for the sins of all those who would believe - the Bible says this:
After This, knowing that all was now completed, and so that the Scripture would be fulfilled, Jesus said, "I am thirsty." A jar full of sour wine was standing there; so they put a sponge full of the sour wine upon a branch of hyssop and brought it up to His mouth. When he had received the drink, Jesus said, "It is finished." With that, he bowed his head and gave up his spirit. (John 19:28-30)
There is nothing more to do.
Chuck Swindoll writes in his devotional Walk with Jesus: A 40-Day Journey to the Cross and Beyond, "With Jesus' last breath on the cross, He declared the debt of sin canceled, completely satisfied. Nothing else required. Not good deeds. Not generous donations. Not penance or confession or baptism or ...or ...or ...nothing."
To quote Augustus Toplady, "Nothing in my hand I bring, Simply to the cross I cling."
You simply need to REPENT (turn from your sins) and TRUST in the Savior.
See: “It Is Finished!” Jesus Does Not Need Your Help | Tetelestai by Tony Miano http://carm.org/it-is-finished