What's the best way to protect the tub when you are tiling the shower enclosure?
What I done in the past is to place a heavy tarp or a small lite rug the size of the tub in the tub and tape it to the tops of the tub so that when tiles fall they hit they land on the tarp or rug. Otherwise, you can use plywood sheets 1/2" or thicker on top to cover the tub too. Plywood works the best because you can stand on it and it is level. Just need to know if you have shower sliding doors or not! If you do; you need to remove them before the tiling begins.
You can still do it without protection if take the wall tiles out one by one if they are small size tiles and remove them by hand.
This is a new bathroom & tub, and no there are no shower doors.
I am more worried about dripping thinset/grout etc. I am a messy tiler, and tend to get it all over myself and the floor, then step in it etc. I've tried taping plastic bags before, but that didn't work work well.
I was told about a product you paint on the tub then peel it off later, but it is very expensive.
I bought a roll of 3 mil plastic at the store today and am trying that. Will see how it goes.
I taped the edges of my tub (acrylic) and taped down plastic and then a painting canvas. I think I put cardboard in the bottom of the tub (on top of the canvas) to help minimize grinding thinset grit into the canvas and possibly scratching the tub. It was my first tiling job, so I was an incredibly messy tiler. I found that I needed plenty of slack in the canvas to keep from having it pull away from the tub. The thinset is fairly thick (not liquid) so the mess usually seemed to be gobs and grit. It took me a while so I would regularly pick up, vacuum up the dried blobs and grit.
Tape the poli down with painters tape and put something solid on the tub base. If you don't have something solid to stand/sit on, you'll invariably end up pulling the plastic away.
Keep a bucket of water and wet sponge handy to wipe up any drips that sneak by. Also, a little prep goes a long way. Get all of your supplies within reach so you aren't in and out of the tub a million times.