So far as I am aware it is as it sounds when written it full - etcetera. Short e (eh), short 't' (te as in 'hit'), 'set', 'er', short 'a' as in cat. Never really done phonics, sorry, near as I can get.
My Latin teacher (who wrote a textbook on the subject) wouldn't!
(Roughly in between "eh ketera" and "eh kaytera", with the 't' of the first word definitely remaining silent).
However I agree that the Anglicised version is 'etsetera'.
Thanks to those who have pointed out the "et kay-tera" pronunciation, which I'd almost forgotten.
How many of you will admit to the awful (giggles) variant I often hear, of "Ex-etera"?
I have heard it pronounced - purely as a joke and always doubled - close to the opening three syllables of the word, 'etiquette'. Thus, ettiki ettiki, with the two letters 'i' as in the word, 'sit'.
David Mitchell did a good sketch on this subject, where he becomes irate by people saying ek setera and also expresso (for the coffee), pacific (instead of specific). I'm sure there were others but can't remember them now.