You're a brave individual!! Been there... Done that... My results
stunk... Floating sheetrock, in my opinion, is an art and the only way
to get it done right is have an artist do it. While it may cost more,
I ALWAYS hire someone else to float it. It is sooooo much nicer and
sooooooooo much easier for me!! In my experience, whatever I paid
always turned out to be well worth the $$. In any event, though, I
wish you well and hope your results turn out great!