In my experience the focus needs to be on loving God. If we focus on the sin we will never overcome the sin in our own strength. Love God, consider all that He has done. Invite the Holy Spirit to fill you. When we are in love with God as revealed to us by Jesus, and filled with the Holy Spirit, we can live lives without sin. Sin is birthed in the mind so if we guard our minds, and surrender our thoughts to our saviour, we can live victorously. Don't be too hard on yourself if you fail, just dust yourself off and get back up again. Jesus died for every sin past and future. He loves you and wants you to live victoriously because He knows the damage that sin causes.