If you prayed that prayer from the depths of your heart, the Bible tells us that God will speak to your heart very soon (Rom. 8:17). He will let you know that He heard your prayer, has forgiven your sins and that His Spirit is in your life now. God's Holy Spirit in you will do amazing things to make your life so much better. For one, He will teach you His truth as you read the Bible and listen to sermons, etc. (John 16:13). He will also give you His power to say "no" to your former sinful habits AND "yes" to living in ways that please Him. That same Spirit of God working in and through your life will also help you tell others about what Jesus has done for you and can do for them.