According to Preston Smith (no relation), the core aspects of comedy improv include:

1. Listen – As simple as this seems, it is probably one of the most difficult skills to master. Listening will free you from having to think of what you are going to say a head of time.

2. Agreement (Yes, And…) – Assuming you have listened, you will be able to agree with what was said AND add information. Agreement is what allows a scene to progress!

3. Team Work (Group Mind) – Improv is a vast mechanism of give and take and support. The group mind is greater then the individual.