Yeah, what Wicked said was good.
1) Remove yourself as much as possible, within reason, from social situations in which you'd smoke or feel compelled to smoke
2) Find a replacement for the action/behaviour, whether it's chewing on pencils (ew), sucking on sugar cane (mmm), or chewing gum (but take care of your jaws) -- taking a drink from a water bottle can work
3) Eat new foods, varied foods, fruits and vegetables
4) Relatedly, introducing other forms of change into your life may help, unless you're the kind of person who gets easily stressed out about that sort of thing, in which case obviously don't do it
Stay the hell away from babies.