Comb out your dog first. Combing your dog's coat daily or every other day will keep most mats at bay. Simply brushing, as most literature instructs, is not enough for dogs that can mat up: the brush will easily pass over at angles that a comb will get stuck on. A thorough combing should always be the first step of the grooming process because any mats will become tighter and less manageable once they dry. Begin on the head and move down the body. Be careful under the belly, as it is a sensitive area, and don't forget to comb the tail.
Clip the dog's hair methodically. You can place the blade against the body safely, so long as you don't press the blade strongly into the skin. Brush against the direction of hair growth(back-brush) before running the clippers the other direction; with the direction of hair growth. Using the clippers against the growth of hair will have the same effect as back-brushing, but will leave a shorter length than the clipper blade that you are using. If you want to shave against the growth of hair, a blade size gets two blade sizes smaller when cutting against the grain. For example, when cutting with 4# against the grain check how long a 7# leaves behind when cutting with the grain. Move the clippers surely, but slowly across the dog's body to remove the hair — moving too fast might leave uneven lines. Always move the blade with the direction of the hairs' growth unless you want a shorter length than your blade claims to leave. Begin at the neck, then move down to the shoulders, under the ears, and toward the chin, throat, and chest areas. DO NOT use a size seven or any skip blades around the throat area or any flaps on the body that can fit between the teeth, such as the Achilles' tendons, arm pits, genital area, tip of tail, or anus. Then, clip the dog's back and sides. Finally, clip the hair on the dog's legs. Be careful when cutting the neck with any blade as it's the most dangerous to cut. Never cut straight down, do so at angles to avoid flaps you can't see in the neck getting cut.