We can't save ourselves from sin and the inevitable death that it brings. We are only saved through a gift from God - the gift of His Son and His Son's sacrifice. It is useless to perform good works to try to save our souls. We can and should do good things, as God has prepared each of us, but we should do them for God's glory because He has already saved us.
God has already saved us, so why would we spend time uselessly trying to re-do what God has already accomplished? Accept forgiveness through Jesus' sacrifice and don't brag about what you have done. Take time you have to praise, pray, and serve God for what is already done and so that others will know of His glory!
Prayer:
Dear God-
Thank You for saving me so that I can have eternal life with You. Allow my works to be in praise and honor of You and what You have done for me. Help others to learn of Your glory through me. In Jesus' name I pray, amen.