This improv game is in the following improv game categories:
You are Simon, and you tell the players to do exactly what Simon tells them
to do, but only if Simon`s sentence starts with "Simon says". Any time
a player does what Simon tells her to do, without preceding that with "Simon
says" is out.
Tell the players
the game starts when you say "Simon says the game has started". Then try
to trick them into doing stuff they`re not supposed to do. Ask them e.g. if
they understand the rules; whoever nods is out. Try telling players that are
out they can join in again; if they do they`re out again.