Link to an improv forum.
http://www.improvresourcecenter.com/mb/showthread.php?t=63457
- Any little thing that strikes your interest can be used. It can be as simple as a location that was mentioned, a relationship, a situation, or an odd turn of phrase.
- When listening to it, I was told to have an opinion and react to what is being said. This will help you remember it, and help you find characters and their "deal" or their "game" or their philosophy faster.
- Rather than replay the idea you heard spoken, swap out the "noun" for other ones-- using the idea of "if this is true, then what else is true", creating similar situations/reactions.
- As was said before, pick out details from the monologue to start a scene. One note I like to give when working on monologue deconstructions is to make sure to pick just one detail to start your scene. Generally avoid taking two different interesting things and combining them.
- And listening with your eyes is as important as listening with your ears. Look at body stance, how does this person feel?