This will be extremely brief! If you have a young cat who bites you too hard when he plays with you, you can stop him or make him take notice by pretending to be hurt. This means screaming a little. Doesn’t have to be too loud. It can be a pretend scream. This replicates what happens when kittens play and play too hard. The cat who is unhappy about the play because it is getting too rough, screams. This is the way kittens learn how hard to bite.
That is my theory. I use the technique with Gabriel as he likes to nibble my hand when we play. He can become excited and bite too hard. It isn’t that hard but too hard so I pretend it hurts by making the appropriate sound. He stops.
You may well think this is a failure and stupid but I find it reasonably effective. I believe it is a decent technique. And it is a gentle technique, effectively a request.
The photo is Gabriel enjoying climbing outside in the evening sun. He is athletic. I am a bit anxious about him but so far it is working out nicely.