First thing I'll say here is that you aren't involved in a Start-up, but a 19th century business. Exhibitions became all the rage after the success of the Great Exhibition in 1851, but they have generally declined in importance as other communication methods have risen. But I'm assuming from the way you've written it that you have an old-fashioned boss, it wasn't your idea and you simply have to make the best of it. If it was your idea, you should cancel it and resign - it most certainly isn't the way to run a modern startup.
If your marketing is at all good, you should not meet any new potential customers at the Trade Show - they should already be aware of you and what you do, including what you can do for them. But there is an opportunity to turn those online contacts into face to face meetings, physical demonstrations and contacts into partnerships.
So start by building some hype. Make sure everyone who knows you - customer, influencer, trade contact, even competitor, knows you are going to do something exciting at the show. This means multi-touch teaser-style work to build excitement, to ensure they know where you are in the show, that something is going to happen and that they will get privileged access and first sight.
Then create that happening. People don't want to see "this is our standard line-up, first unveiled a year ago" - they want something new. And while it is nice to see physical products if you have them, they want to see what they can do - ideally what they can do for them. So turn the show into an action event. Host a launch. Do demos (if it is small and demos need to be one to one, get people to book their slot). Have a trade evening where you talk to potential suppliers. Or a media evening where you talk to the newspeople and help them generate stories.
And make it interactive. Create a "design our next generation of products" challenge. Find ways to get them to come up with ideas, tell you how they use it, what problems they have which it will solve and what problems they have which will not be solved and still remain.
Also target some key people, you know are going to be there. Try to use the "we're both there, so let's talk". Build a list of your top hundred potential trade customers, top 100 influencers, top 100 media people and try to use the show as a way to get to talk to them. Use the show also to generate stories in media around Launch, New, etc. And get it on your blog, multiple times with different angles - "why we lead the way in what the show's about", "how would you do things differently - come and talk to us at...", "ten things about this field" etc.
Finally, don't go phew, that's it, when it is over. Get out there and use those leads to meet people. Send them a thankyou for coming to our stand gift and voucher off a future purchase. Open up partnerships with the trade and exploit those new relationships with the media.
You can make a show into a media and partner event, which really puts you on the map. Or you can waste a week standing in an empty booth. Choice is yours.