A sturdy tripod and longer exposures are good things to start with. The rest is going to depend on where you are shooting (amount of ambient light), your camera's available settings, and the style of photos you want.
Everyone's got their own opinion on how to shoot these. It seems that really long exposures seem to be popular with most people. Personally, I don't care for shooting them that way because your images are just blurs and streaks of color. They are pretty, but I don't think they look like fireworks. I decide just how fast I want to expose by where the fireworks show is being held. If it is somewhere scenic, do longer exposures so that you can capture the surroundings. This may be downtown, on the coast (see rusty's photo with the water), Disney World, etc. If shooting them in a small town and there aren't any cool surroundings, I tend to shoot a little faster and get a more "realistic" photo of the fireworks. It is harder to capture them this way becuase of the obvious timing concerns, but it's not as hard as it may seem. If you camera has a bust mode, you'll be fine.
Here's a couple shot with faster shutter speeds. I like these because they look a little more "real" to me. These were both shot in small towns where there wasn't any cool surroundings I wanted to get in the pictures, so I just decided to expose quick enough to capture the fireworks at a decent speed. The top picture was shot at 1/160, f2.8. The second picture was shot at 1/80, f3.5.
The next couple shots were taken in downtown Houston last year and I wanted to do longer exposures to capture the buildings. Both of these were shot at 1 second, f5.6. A longer exposre at a smaller aperture (higher f-stop number) and slower ISO speed would have exposed the buildings better, but I would have more fireworks in each shot and they would have been blurrier and more streaky.
I still haven't perfected this yet - don't get many opportunities to practice. I would suggest getting your tripod set up in plenty of time and making a list of different exposure settings to experiment with so you can determine what kind of pictures you want. Shooting digital will allow you to see you images instantly and adjust them accordingly. Pay attention to the wind direction because if the smoke is blowing towards you, you aren't going to get any good shots at all! If you camera doesn't shoot "slow" enough, you might want to look into purchasing a neutral density filter. This won't change the light/colors any, but will simply reduce the amount of light hitting your sensor allowing you to make longer exposures. I know this is a problem with many digital cameras.
Hopefully some other people will chime in and share thier techniques as well. I'm still learning myself!
I wont have access to my old firework hotspot this year
. So I will need to find another good location. I plan on using this weekend to scout some places out (anyone have a good spot??). I use to have a sweet location to photograph fireworks (my inlaws backyard). But they moved, so now I am on the look out for good places in town to shoot. I didnt realize how good of a show, and how good of a location I had until I started thinking that I couldnt watch the show from their backyard anymore..
Like fishphoto said.. best thing is to shoot, review, and then adjust settings if necessary. A couple of basic things that you will need to do regardless though.
1.)use a tripod
2.)set white balance to sunny
3.)set your ISO to 100
3.)set your camera mode to shutter priority (S mode on sonys, Tv mode on canons, not sure on other camera brands)
and now is when the variable factor comes in.
4.)set your shutter speed. fast (eg 1/100 sec) for just the burst of light (like fishphoto) or slow for the long trails. By slow, it can range from 1 second all the way to 10 seconds (or even more).
Try to avoid bright street lamps in the immediate foreground. If you cant avoid them, then a faster shutter will probably render better photos.
Usually once the firework show starts, I just point the camera to the sky, and start pressing the shutter. Usually I try to time the shutter press with when I hear the firework launched.. but a lot of it is just luck.. just keep pressing the shutter.
Those shots I took were on Waugh/Heights Blvd/Yale (can't remember which ones merge before or after) where it goes over Memorial. There is a little park down there. We just parked on the road and set up on the northern side of the overpass. That provided a pretty good view of downtown as well. If I remember correctly those shots were all taken at 17mm (30mm equivalent on digital), so it is fairly close to downtown. You don't need that wide of a lens - I just wanted to capture all of downtown in the images. I may end up going back there this year if I decide to shoot the downtown show. I may stay up here and shoot the one in the Woodlands though.