It's all about the Set move.
Remember: Anything's an Offer.

A group of improvisers gather pre-show. They take off excess clothes. They empty their pockets. They ask about each other's day.
One guy tells a story about an out-of-the-blue run-in with an old friend that happened that day.
Another improviser tells her own story about an even more random out-of-the-blue run-in with an even older friend.
And an organic warm-up is off running.

An improviser notices two of his compatriots are bent down tying their shoes so he mirrors them. A fourth follows. A fifth.
And an organic warm-up is off running.

An awkward group of improvisers gravitates into a pre-show circle, wanting to find something organic, not wanting to force anything. One guy starts mirroring another's nervous hand wringing. A girl coughs so someone else does. Someone laughs. They all laugh.
And an organic warm-up is off running.

Groups have the best shows after playfully finding an organic warm-up together. Try it.

It can help to have a few simple go-to warm-ups to get the ball rolling - Crazy Eights, Ronin, Banana Naming. Get on the same page but feel free to follow mutations.

A dedication to Kick The Duck, Red Rover in practice helps attune a group to finding and following organic patterns.

But if ever 'twas a trusted catalyst for one improviser to spur her group into an organic warm-up, it's the Set move. Heighten something already established. Heighten it enough to ensure someone else sees it.

Steal a Story. Mirror (but don't mock). Agree wholeheartedly with something said. Commit hard to recreating something physical the first person did subconsciously or accidentally.

A point becomes a movement when it is joined by other points that define its direction.

Build a movement. Follow and heighten.

Have fun!