I recall being quite red-faced in college when a professor, exasperated, asked why on earth I would spell Goethe’s name with an ö. “I bet it’s just because you figured how to do that with your word-processor.”
Ä = 0196 ä=0228
Ë = 0203 ë=0235
Ï = 0207 ï=0239
Ö = 0214 ö=0246
Ü=0220 ü=0252
Ÿ=0178 ÿ=0255
On an Apple platform, it’s a bit more intuitive, just taking the Option key—or on a touch pad, just depressing the letter for a bit longer. For script, it’s the letter (Capitalized or lower-case) and uml(aut) preceded by an ampersand.
There is, however, the potential for minor irritation with spacing and kerning, even in the Sprachraüme, including Turkish, that use such accent marks. One particular Autobahn sign, which I pass on my way home, employees this funny, glaring non-standard g in order to accommodate Umlauten above and below. One would think that Germans could improve on this layout. Sometimes one finds stylized typefaces that minimize these effects without detracting from the sound or meaning imparted with vertical or embedded dots. If there’s ever celebrities or world-leaders with a lot of umlauts to their names, some clever person should make such a standard alphabet for newsprint and make it freely available. If I am able to figure it out, I will surely share.