A simple warm up exercise that is really good for getting improvisers connected to each other.
Everyone in pairs stood opposite their partner.
One of them can move however they want. The other is being their mirror image, copying their emotions, face and movements.
After a couple of minutes swap over roles so the leader becomes the follower.
After a couple of minutes both pretend to be followers, so you find it together.
As a variation you can also continue this and find a character together by copying and escalating each other’s body language, gestures, sounds and mannerisms.