ich bin in china jetzt.ich kann neue voerter gleich in spelling.o=ö u=ü i=ï e=ë ss=ß

If it is not on your keyboard press shift for capital and ", and after that press a, o, u, i, or e. On your screen you will see ä ö ü ï ë. You can also use "asci-codes" For each caracter there is a combination of "alt" and 3 numbers. So keep "alt"-key pressed aand type 225, and you will get the german caracter ß. So for every caracter is such a combination. You can find that asci-codes in many computer-books.

Like everything else, it's pretty easy on a Mac: Alt+u and a, o or u (or A, O, U for capital umlauts). (Alt+u indicates that the next character should be decorated with those two little dots)

Under windows and linux you can use the "Character Map" program. Mac has one too I just recall what is atm.