Hooch I have used a number of different carving techniques.

Xacto knife - Works well but slow and can cause breakage in smaller areas due to pressure.

Dremel Tool - Works great and quick.. Need small bits for details and creates alot of "dust" but this is what I use mostly

Hot Knife - Its just like a wood burning tool with a flat blade on the end. This works very well as well but it creates fumes so you have to do it in a well ventilated area.