Get a Clipper quiet enough that does not scare the dog. (You will also need a slicker brush and a clipping blade - a number three that leaves the hair about 3/4 of an inch would be good to go)
Turn your Clipper on and start at the back of the neck and be very methodical. You don't want to push your Clipper too fast, that will leave lines.
Always flip with the growth of the hair.
Hold your buddy tight when trimming.
Start from the back of the neck, the whole side of the back legs, and then continue on the other side of the body — the back leg and then, finally, the front legs.
Then you can get the belly real tight; you can go against the grain on the belly here.
It will usually take about 15 minutes to shave down the dog.
If you do notice that it's not picking it up enough coat, you can back brush with your slicker brush to get a more even look.