Guys, this is a Newbie section after all
1) I would say that one of the best ways I have found to tell is the amount of English they speak. The more time they have in the saddle, generally speaking, the more English they are going to know.
2) Another way, is the bolt ons, that takes a few months of funding to purchase.
3) Hard core demeanor, u buy me drink, cigs, my friend a drink, cab fare etc etc etc. You have to spend some time in the life to get so freaking rude.
4) War paint, battle dress or lack thereof. Newbies should not have those attributes.
Hope that helps.

Good answer TB.Stun since you can speak the language you might be able to size them up a little quicker.(hop on that plane and get on the job expierence amigo)!