As a former smoker who quit with the patch AND Wellbutrin, I don't have a lot of room to advise. But, after smoking for 20 years, I had cravings, even with all the extras to take the edge off. Here's what helped me:
Drink lots of water or herbal tea. It will help flush out your system, and it gives you something to do with your hands and your mouth.
Do not use caffeine or alcohol, not even a little.
Try to stay away from sugar. It's tempting to substitute hard candies or some other type of candy for the cigarettes, but when you get done eating the candy, the craving just comes back, only stronger because you're getting amped on sugar. So you end up eating more and more and more candy, and the cravings get tougher and tougher -- viscious cycle.
Personally, I'd eat ultra-low fat for at least 4 or 5 days. I did the McDougall Diet when I quit smoking because you can eat almost constantly without feeling bloated. Eating 5,000 baby carrots a day gives you something to to with your hands that doesn't give you a sugar high.
Breathe. When a craving hits, take long, slow deep breaths. It will make it seem like the craving doesn't last as long.
Be patient. When you quit cold turkey, it takes 4 days for the worst of the physical addiction to wear off. After the fourth day, it gets a lot easier.
Finally, if you fail, forgive yourself, recognize the trigger that led you to fail, and try again doing your best to avoid that trigger next time.