I was wondering how one would pronounce the W on it's own.
It rarely occurs on its own. When it does, it's like an English v with no vowel following. Most of the time, attach it to the following word and if the first sound of the next word is p, t, k, ć, c, cz, s, sz then its pronounced more like f.
w ciemności = fchyem-NO-shchi (with vowels like Spanish).