At a trade show it is all about show business. The company that can create the nicest booth, put on the biggest show and have the best free giveaways will draw the biggest crowds. One effective way of drawing people to your trade show booth is with games. Several different kinds of games can help you draw an interested crowd.
A miniature golf course at your trade-show booth that gives prizes for the best scores is sure to draw a crowd. You do not need to create a complete 18-hole putting course, but you should have at least three or four putting greens available so that people don't become discouraged waiting to play. Post the best scores on a golf leader board at your booth, and you can collect business cards as greens fees.
A balloon pop game is effective because it is fun, and it is loud. The sound will be sure to draw people to your booth, and the people walking away with prizes will also help develop interest from a trade-show crowd. Set up balloons on a cork board, and allow people to pop one balloon in exchange for a business card. Try to make sure each balloon offers some kind of prize, and be sure to collect the pins when the popping is done.
The spinning wheel offers a bit of the carnival at your trade show booth. As with the balloon popping game, the spinning wheel is effective because it is loud. The clacking of the wheel as it spins will be sure to draw a crowd. You could even set a theme with the wheel and have the booth attendant who is running the wheel game dress up in an old carnival outfit.
The reason the ring toss game is effective at the carnival is because it looks easy. The same principle will work at your trade-show booth. Set up a ring toss game where people exchange their business card or contact information for the chance to throw a ring and win a prize. The larger your ring toss board, the more attention it will gain.