Here’s a really simple dog training tip to stop your dog play biting without punishing him (e.g. by putting him in a crate). This tip was taken from the Dog Training Planner.
Outcome: Stop your dog biting
Step 1: Leave Room
Remove yourself from the room long enough (approx 30 seconds) to let your dog reflect on the biting that lead to the lose of their favourite human playmate.
Step 2: Re-enter Room & Pat
When you come back into the room, talk to your dog and pat him. You want your dog to know that you still love him. It’s just the painful biting behaviour you find intolerable.