How to dismantle the keg for cleaning / sanitising, tools required, advice on cleaners appropriate for the purpose and what is definitely not best left in contact with cornies for prolonged periods. Probably worth explaining why it's better to seal a keg at 30PSI rather than hit it with 10PSI and hope. Explanation of the dangers of filling beer above the in post dip-tube (as I found out AGAIN tonight, I should know better), basic guide to carbonation (I mean very basic, beer temp + 3PSI for two days, drop to 6-10PSI thereafter). Finding leaks, various gassing options available, advantages and disadvantages of the various gas options, gas regulator instructions, identifying in and out posts.
That should do it for starters. :)