This is what I do with all of my dogs when I introduce the nail clippers and electric clipper... I let them see it and sniff, I won't use at this point, each time I bring a nail clipper or electric clipper out I give them a treat and let them know they are good for just not being scared of it. After a week of that, I will put object close to the body where they have direct contact with it and once again reward and encourage them and do this for another week. Finally I will start to clip a nail, a tiny bit at first and reassure them and reward them and then move on to where I can clip their nails with no problems. It never fails, all them are trained and the vets and groomers love the fact that they are so easy to work with. It takes time, but it works without getting your dog or you upset. Nail clippers can be a scary thing for a dog, you just have to build up their confidence and reward them for it. Never hold a dog down, it will just tramuatize them and will make things alot harder.