Onstage, the choices are limitless when there is no script. By severely limiting your choices, the storyline becomes more focused and more easily followed by both audience and fellow improvisers.
When a group of improvisers are working together, a response of "no" within the scene quickly stops the action. By abandoning this word and always using "yes," the storyline can only proceed.
Rich characters provide more depth to a storyline. By creating the physicalities of the character first, you can work backwards in developing the rest of the character (opposite to script acting).
By asking questions in an improv scene, it might become derailed by the other actor trying to answer the question. In improvisation, accepting whatever is happening and moving forward is the best rule to a successful scene.
Repetition onstage can be vital to remind the audience; however, excessive repetition becomes cumbersome. In improvisation, "the rule of three" states that if a word (a phrase or comment) has been said three times, eliminate that idea and develop something new.