Clean it once really good then it is up to you to maintain it. If you allow it to get trashed then it is your fault. Just like anything else in life you get it to the point where you feel happy then work on maintaining it.
chewing gum helps or holding a stick of gum like it was a cigarette helps to but it will ulitmately come down to will power. You can try every method you want if you don't have the will power or desire to quit then don't even bother.