Every guest is different, I'm quite shy (at first or until I've had a drink!!) and some guests will pick up on that and do what they can to put you at ease and converse with you, Brian Krause overheard me talking to my mum in the queue as I handed my pic over to be signed to his assistant, I just so happened to be saying to mum that I thought it was a shame there were no shirtless shots (yes I'm shallow!!) of him like there were other guests and before I could even splutter out a hello he'd whipped his shirt up to flash his beautifully toned tummy and asked me why would I want to see this old thing with a gorgeous smile and a wink, quite how he expected me to carry on a conversation after that I will never know, to this day though it's one of the nicest encounters I've had and the fact that he was relaxed and chilled enough to do something like that was great
Or you could just be a clumsy devil in my Adam Baldwin photo shoot he went to shake my hand I went to put my arm round him, it was all very awkward and I ended up standing on his toes, he was lovely about it, but it had the added bonus that he remembered me when I went to get my auto from him and we had a great conversation about me being clumsy and him coming to the rescue, that and I had an Independence day photo for him to sign so we conversed around that too.
The easiest way is if you are shy and nervous just to go in with a nice polite Hi how are you and you can't go far wrong, with guests from overseas one of the best questions I find is are you enjoying England and are you seeing anymore of it or going straight home, that can lead to all sorts of chats and I once got a restaurant and hotel recommendation for when I visited New York.
And if all that fails just take some one else with you who can chat for Britain and chime in when you need to, my mum is the best she can and will talk to anyone about anything and has no fear she doesn't care if they're famous or not to her they're all just people so quite often if I'm very starstruck I let her go first and start the conversation up and then piggy back onto it from there.
The more events you do the less nervy you'll be, at my first con 12 years ago I couldn't speak for nerves at meeting the stars now there are only very few that render me speechless
Eeeek that post was longer than I intended