How do I lock my presentation on to the screen?

Hi there,

I have an event coming up where I'll have a stall and I want 3 iPads and stand to be around the stall. I've put a keynote presentation together to allow people to come up to our stall and interact with the iPads so that they can get information about what we do. The only problem is, is that I'm using a lot of hyperlinks in the presentation so that it is acting as more of a website or an app than a powerpoint. Because of this people who may accidentally click off the buttons (hyperlinks) will go onto a different slide and at worst maybe exit the powerpoint altogether.

Basically, It would be brilliant if there was anyway that I would be the only one to get off of the presentation.

Any help would be greatly appreciated.

Thanks in advance.