A renovation of a bathroom inevitably involves plumbing. I've described the shower waste connection and the connections for the sink. The toilet water supply pipe I had to send up vertically then out horizontally to the cistern. This needed a bit of pipe bending and a 90 degree soldered joint, but the result is fine, even if the solder joint could be cleaner. With the plasterboard in place and tiled, the effect is quite good. I can do the cosmetic stuff on the pipe and the hole later.
For the shower tap I used a fitting that I've not used before. It claims to make fitting shower taps easy, and it does seem to work. You fix a metal plate to your wall, and two 90° connectors (hot and cold) slot into it. You have to cut matching holes in the tiles of course, but if you do it right, you can take the connecting pipes out for inspection later if needed. (The photo of the metal plate shows the water pipes that are to be connected to the 90° connectors.)