Link still not working.
Anyways, It's rather easy once you get the hang of it.
Aperture
Like tirediron said f/8 would work pretty well. I've used f/5 to f/16 but most shots work well enough around f/8-f/10.
ISO
ISO 400 seems high to me personally... especially at f/8. I usually shoot at ISO 100 and I don't really see much of a reason not to do so. Fireworks give off a lot of light, I've never really had a problem capturing it.
Shutter speed
Here's where things get interesting. The longer your shutter speed, the more fireworks you get in the shot. The shorter, the less fireworks. You could try and set a shutter speed beforehand and then just go about but I find that the best (and easiest) way to determine the shutter speed is in
bulb mode.
While in bulb mode you'll be able to determine the shutter speed manually. The first time you click the shutter release the shutter opens, the second time you click it the shutter closes. This way you'll be able to open the shutter right when you think a nice boom will come and close it when you think the best view of the boom is gone. Note that you will most definitely need a remote for this to work properly, I'll explain why later.
Tripod
You'll definitely need a tripod. Longer shutter speeds and such.
Make sure your tripod is placed as firm as possible and nothing will be able to shake it in any way as you'll be able to see
any camera shake in the photo.
Remote
Using a remote will make sure you can't shake the camera by accident while pressing the shutter button. It is also possible to use the timer function (on 2 seconds for example) but a remote really works best.
I mentioned before that you'd really need a remote when you're using bulb mode... That is because you'll need to press that button twice per photo in bulb mode and the second time is during the actual taking of the photo. If you're not using a remote you will most definitely shake that camera.
Position
It's a good idea to try and find a nice spot where you can easily get a bit of the surroundings in the photo too. Like tirediron said fireworks photos which include some of the surroundings are usually more interesting.
As a last thing: Don't forget to actually look at the fireworks yourself for a bit. Don't be constantly busy with the camera, you should enjoy the show too.
If you're using a remote and got the settings right just enjoy the show while clicking away. ^^
Here's the results I got a little while ago using the bulb mode:
Reinier van Antwerpen - Queensday fireworks on the 'kroningsdag'
