I offer with my open palm at first, and use the word GENTLE before and then GOOD GENTLE after they take it nicely. Then I make it tougher, I will close some fingers on it, and still tell him Gentle to remind him. When he is doing that well, I will then start subjecting only my fingers to the anxious jaws of the treat crazy canine. But I remind with the word Gentle and they get it. I always praise with a good gentle.
Eventually, I praise intermittently and will stop reminding. But if they get too eager, I then use my hurt voice and the gentle word to let the guilty party know they still need to be careful. So far I still have all my digits so it must be working.
Bear Cub, Hepsi-Pepsi
Cujo2, Karma Chameleon
Ramona the Pest, Kojak -- who loves you baby?
Tiny Tinnie, Susie's Uzzi, Kaiah -- The Baby Monster.