Brainstorm different ideas on a piece of paper. Make a list of possible ideas or characters to base the skit on.
Discuss with your group what kind of ideas for skits might appeal to the group. Vote on the entries from your list and eliminate a possibility each round. Take a final vote on the remaining two or three ideas.
Assign a character to each member of the group. Let each member develop his or her own character before interacting with the entire group.
Work on a group script out loud. Establish the set of characters and go to each member for their individual character's behaviors and characteristics. Write a reference list to refer to in case anyone gets lost.
Develop a short summary of the scene to keep everyone on track. You should include a description of the action and what the main characters are trying to accomplish.
Practice the skit several times so everyone can get their timing down. Make any alterations at the dialogue level after discussing it among the group.
Run through the skit a final time. Highlight any physical or slapstick comedy that you are trying to relate to the audience. Ready yourselves for the actual performance.