you want to desensitize the dog to the process... show the dog the clippers and he gets treats, let the dog sniff the clippers and he gets treats. touching the dog's legs=treats, the feet=treats... move slowly, even if the dog seems to be "okay" don't jump to the next "step" right away. work your way up to playing with his toes and that also= treats, play with the toenails=treats... gently squeeze the nail=treat... this will take some time, not sure how long, that will depend on the dog, plan on days-weeks if he is only a little upset by the process, but it may take longer... when you actually clip the nails... take small steps and if you have a helper to feed him treats while you are clipping, that will help quite a bit. don't push it once you get to the actual clipping, if you only clip one nail and he gets a good reward for it, he is more likely to be relaxed the next day and you can clip another... basically, the key is to take it slowly.
good luck
oh and the treats, depending on how food motivated your dog is, you'll want to use something that he considers "high value"
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