I've ripped out my only water closet. I wanted to change the tiles and the floor tiles were laminate which were cracking.

This is my first project so any advice would be grand.

I want to retile halfway up the wall and tile the floor. My steps so far:

1. I took the tiles off to where there was lots of horsehair plaster as well as what looked like old green paint and the previous plaster. 

2. When I took the floor up there was plywood with a sticky resin. I ripped this up back to the floorboards.

 3. I used a primer on the wall and removed any loose plaster. It all feels solid. I also primed the wood so it wouldn't suck moisture out the addy.

4. I have decided to use HardieBacker Boards to create a proper surface to tile on. So far I have the far wall and the right wall with backer boards (less a small strip at the top). The area where the sink is (on the left) doesn't have enough clearance to have backerboard, adhesive and then tile. How else could I do this? Im hoping I can use flexi tile adhesive and adhere tiles straight to it? Similarly, I plan to use tile adhesive straight onto the plywood which is boxing in the pipes. Is this ok?

5. After the backer boards, I have used scrim and then covered the scrim with tile adhesive again.

I think I'm ready to tile. Am I missing anything? Any tips for tiling? How do I keep the tiles up when I'm doing the walls, and prevent them from sliding down?

WC Reno: First time and advice