What if you sin after you are baptized? What then do you do?
We are saved by grace because none of us is or will be perfect. Jesus paid the price for us.
Yet, we are to follow Him and be faithful. When we sin, we ask for forgiveness. We are not given free license to live a sinful life as we now live following Christ. Yet, those that have fallen away, can ask for forgiveness and to be restored to the Church.
I would like yukong or another bible scholar to give you instruction in these areas as I fear I might mis-explain to you. We are all sinners and have faults and weaknesses. But, by faith and prayer we follow Jesus and do the best we can. Forgiveness covers much as we all know.
I John 1:7-10: But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin. If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, he is faithful and just to forgive us [our] sins, and to cleanse us from all unrighteousness. If we say that we have not sinned, we make him a liar, and his word is not in us.