I had a tiny toy poodle years ago that I used to take to be trimmed. She always came back very traumatized. I decided to never do that again.
I have always trimmed my own dogs but now with Angel having such thick long silky hair where I have always had cotton coats that are much easier to trim on my other yorkies. So I decided to purchase trimmers and I bought a cd I ordered from target that goes step by step on what to do and it even has a section on terriers.
I haven't done anything yet but I am getting ready in the next couple weeks since it will start getting warm.