Pip either just... stares, or sits over and over again. Like, S-I-T-S in that butt-slamming, LOOK AT ME I AM SITTING way that some dogs have.
Maisy just gets more and more intense and focused but eventually something breaks and she gets all wiggly instead.
Squash... oh, Squash. Sometimes he will roar and jump up in the air. Not jump ON me, but just sort of pogo stick. Often ending with a nose punch to my face. Usually that's either when he's learning something completely new or when he is getting bored of training. Sometimes, usually if we're practicing something relatively new to him but that he does "get" but hasn't mastered, he gets this real odd look on his face that's like a combination of deep thought and complete vacancy. Then he'll either reallllly slowly ease into the correct behavior, or start enthusiastically doing semi-random tricks or behaviors... sit pretty or flinging himself into a ridiculously dramatic down are the most common.