I've managed to quit a few times, and have learned a few tricks along the way. This time was harder than all the others, so I resorted to a vape. I was always against the idea, but this way I can at least move down in nicotine levels until I've got it completely out of my system and only have to deal with the oral fixation issue.
The thing that's helped most though is my mindset. Just saying, "No!" to yourself is going to stir up your inner child, who will have tantrums and try to convince you that you're wrong. So focusing on all the intrinsic rewards will keep those feelings of loss at bay. Notice your breathing. Notice your senses heightening, your clothes smelling better, your body finally feeling hydrated, your skin and hair looking better, all the time and money you're saving. Feel sorry for all the smokers you see torturing themselves by having to be in the cold. Remember all the times you were stressed out because you were unable to stop what you were doing to have a cig. Everytime you have a chance, but don't take it, let yourself have a moment of pride. After taking this approach I started to forget that cigarettes even existed. It helps of course to have a good support system. Your friends should also be invested in your progress, rather than being the source of your temptation.
After you successfully quit, try to remember how you felt on and off of cigs, and appreciate how hard you worked for your new life, so that you don't have to be like me, and just undo it all again.