THIS!!! Plus, the more your handle you snakes, the more you'll get a feel for their individual personalities. Some tolerate regular handling, and become very relaxed. Some never really take to it much. The key is learning your animal and being able to read it's stress signs.
and THIS!!!
Just make sure you support their whole body when handling them and come from underneath the head with the shy or nervous snake.
/EDIT/ And watch out for "sausage tail"...or be prepared to get pooped on.