What ratio sand and cement do i need for a bedding mix for my bathroom floor. do i need bond crete as well?

Question:I have ripped up my old tiles and need to do a bedding mix to get the fall i need. what is the best product to use. Do i have to wait for the bedding mix to go hard before i lay my floor tiles

Answers:
Trying your hand at a wetbed, eh? It can be tricky if you haven't done it before.
Your best bet is to use a mix of sand, portland cement and water. Approximately a ratio of 2 parts sand to 1 part cement.mix the 2 dry ingredients until well mingled together. Then begin to work the water into the mixture...I cannot give you a precise amount of water to use, however the resulting mix of water, sand and cement should be 'firm' in consistency.not dry enough to fall apart when squeezed into ones fist and not wet enough to be 'mudlike'. I'm sorry for appearing vague, but after doing it so many times.it just becomes second nature, I don't really pay attention to precise amounts. If its too dry, it won't stay bonded and if its too wet, it will not cure properly and is a bugger to try to smooth and get the desired pitch.
I can tell you this as a certainty, however...yes, definitely give the mixture time to harden completely before even thinking about laying tile on it.