Time for a quick revisit to a post I wrote just about 2 years ago titled "The Star Wars Cantina" . The message then is the same message now - and worth repeating. If you are going to exhibit at a trade show, you have 5 seconds or less of a passer-by's attention to say what you do, the market you serve and get them to pause long enough to start a conversation.
You've got to stand out - not with contests, drawings or give-aways - but with crystal clear messaging. (or do both if your budget allows, but always the messaging). I'll give you my example. If I had a booth at a show that was going to attract my target customer - small businesses - my headline banner would read " We help small businesses stop wasting money on marketing" Then under it, my company name, then in smaller font, a tag line that would read "Marketing that gets Results". My headline says who my ideal client is and the problem I solve. They can read it quickly and decide if that is something they are interested in. It invokes a question - "how do you do that?", and that question is how you gather prospects at a show.
So if a tradeshow is in your plans, take a long hard look at your messaging. Tradeshows are hugely expensive for small businesses (the floor space is usually only about 20% of the total cost). Make your booth work for you.