Sins against Linguistics in SF/Fantasy

[wm.annis]

How is an ejective s pronounced? like a louder S?

No, it has the same airstream mechanism of the ejective stops we know and love.  Namely, the glottis is closed for the enunciation of the /s/, then released for the vowel.  Ejective /s/ is a pretty rare sound.

Ejective /ts/ is fairly common in languages that have ejectives at all, and you might have an easier time producing an ejective /s/ if you start with ejective /ts/ for practice, then remove the /t/ later.

Heard of Nuxálk?  It was made with plenty of vowel-free words (although a lot of voiceless syllabic fricatives exist, so it is not as bad as the above).

I have, and so has Suomichris.  I'm guessing most SF authors have not.