Installing apps without wifi

Hi,

I have a 4th gen. iPod touch and I want to install a new app at work. There's no wifi, so I would have to install over the iPod cable (or bluetooth if there's any way to do that). I've downloaded the app to iTunes and I know I can sync my pod and get it in that way, but when I go to start that, iTunes tells me that it will clear all the info from my iPod apps and replace it with info from the ones on iTunes, which I don't want to do, since that would wipe out any work I've done on my iPod. What can I do?