Getting started with clicker training?

I have a 6 year old Bearded Collie who I'd like to start clicker training. He is wary about having his feet and nails touched and I'd like to know the best way to get started. I have the clicker, I have small treats. I have clicked, treat, clicked, treat, clicked treat and now he sits for a click. How do i get started getting him to accept Dremeling?