A little thing that works for me, I used it to quit snuff and I'm using it now to quit drinking is whenever I feel the urge and a lot of times when I don't I say to myself.
No thank you. I don't drink.
It is sort of like a gun fighter practicing his quick draw techniques. It is a statement of fact and by repeating it it becomes a reflex.
To paraphrase Bruce Lee. I don't have to say it, it says itself.