I would flick the light if I want everybody's attention (as in deaf school, deaf event, etc.) If it is just one person, I would go to that person or wave at that person (if another person next to the person I want, saw me and he/she can tap the person I want for me.)
Outside, I would go to the person. If I want everybody's attention, I would wave my arms and sign "watch me". The people who saw me first would alert the others.
