I'm a German speaker. English speakers, try to say the following, slowly:
FOOL-cull
That's about as close as you can get within the phonics of the English language. The "oo" component of "FOOL" would have a slight tweak at the end, a hint of the letter E, as the letter ö, which indeed spelled out (as in the case where there is no umlaut on a typewriter), would be "oe" as in "Voelkl."