The Reign of Grace - Reckoning Yourself Dead

So here is my situation. Sin is no longer in my spirit. I am changed. I am a new man. Christ lives in me. And where the Lord Jesus lives… it is holy… it is pure. But sin is still is at play in my flesh and I am more aware of it than ever. I hate it. It is not what I want. But to often it is what I find myself doing. What can I do? What is the next step? What do I do when sin comes upon my flesh? Comes at me?