There are sometimes discounts for pre-registration. Plus, you get to find out about the hours, rules show layout, other exhibitors, and any workshops in advance. Stand in a long, slow-moving line to present your identification. If you can't pre-register, then do as much research as you can before you get to the show. Few things are more frustrating than flying or driving 10 hours, only to find out that you can't get into the show.
Business cards are one of the least expensive forms of advertising available.
If you haven't gone to a show outside your area before, you might need more information on your business cards. If your business cards are for your own local craft shows, you may have intentionally left off your address or other information. Your business name and your name. Your fax number and e-mail address, in case you want someone to contact you quickly. If you're promoting a trade show that you think they might not know about, they would probably be happy to hear from you.