So... Tonight is RiverFire in Brisbane... and I want to go get some great shots... But as I'll be on foot and there's no room for a tripod, does anyone have any good suggestions or tips on taking photos of fireworks?

So my guess is that because I don't want to stall on the camera trying to focus when its dark, I put it on manual focus and have it on infinity (the max focus), ISO I'd set would be possibly around 400 - 600, Biggest aperture and then shutter speed of about 1/25 (I've found that my hands arent yet terribly stable to take any slower speeds yet.

So please tell me if I'm going along the right track or if there are any good tricks to snapping fireworks