Keyboard question

I need to be able to type umlauts (äöüß) on Safari.

Is there any way I can do this? I already know option+u (ü) and alt+s (ß).

I need an easy way to type these.

Thanks!

Try using the OPTION key. As you have found holding down OPTION and ‘s’ gets ß. For the umlauted characters hold down OPTION and push ‘u’, then type the desired base letter (a, o, u, A, O, or U). The umlaut will appear over the letter you typed.
You can also use OPTION 'e' and OPTION 'i' for other a, e, i, o, u variations.

If you're running Lion, just hold down the letter for which you want to add the umlaut (or any accent for that matter). You should see a list of options appear in a bubble of the letter, much like you would in iOS.