With a digital SLR they suggest to use a slow shutter speed which means you will also need a tripod (I still dont have one, but hopefully soon!). Get a shutter release cable (I don't have this either....) to reduce any camera shake. Reduce the ISO (film speed) to the lowest level to reduce graininess, turn off auto focus and use an f/stop between f/8 and f/16. Sounds tricky to me, but hopefully I can still try to get some good shots without the tripod and the shutter release cable. Interestingly, for those of us without tripods, here is another hint: Use a faster shutter speed and a higher ISO. You will need to re-adjust your f/stop so that the images wont be too dark. These pictures will be a bit different in that you wont have light trails from your fireworks, but there will be a higher level of detail.
For more tips on using different kinds of cameras like the point and shoot and iPhone, click on the links below! Also, check out this book that has a few pages on how to photograph fireworks
as well as other really great tips. Have a happy 4th!