[header] How to act around a celebrity [title] Learn about them ahead of time. [step] If you aren't the celebrity's number one fan and don't know much about them, learn about them before the meet and greet. Maybe you won the meet and greet tickets on the radio, but don't know their work or you love the celebrity but you don't know much about them. 
If this is the case look up information about who they are. Watch their movies and tv shows, or listen to their music before the meet and greet so you are prepared.