1. Rolling over and showing his belly
When your dog rolls over onto his back and shows you his belly, it can be sign of submission, fear or even an attempt to diffuse a stressful situation. Research has shown that dogs will display this type of behaviour when they don’t want to be considered as a threat to other dogs. In other words, they will roll onto their back in submission to show that they are not about to attack and are therefore not a threat.
So when your dog does this, he is telling you that he trusts you and wants you to trust him too! He may even like to have a belly rub!