I was exactly this type of smoker and these are the steps I took:
1. I announced to everyone that I was quitting. That way all of my friends could make a choice to limit their smoking around me and keep me honest in my goal to quit smoking.
2. Took myself out of situations where I would be tempted to smoke. Don't go outside the bar to carry on the conversation with the smokers.
3. Joined the gym. Exercise is amazing for warding off the physical temptation. Your body is flooded with natural feel-good endorphins. And, you know, keeps you in shape.
But most importantly you have to really want to. For a long time I knew I should but I enjoyed the act. I got to a point where the gross feeling of having smoked far outweighed any enjoyment I got out of the act of smoking.