Building codes and get those municipal construction notices if necessary. Dumpster rental? Haul? I would talk to city/town first and find out what needs to be legally.

Then: Walls. Insulation. Moisture barriers. Check for mold. Electrical upgrades. (wiring for appliances, lighting, supply sockets) Ventilation. Heat/AC supplies/returns.

Then plumbing. Not sure if you are going to pre-purchase large items before install? Just be sure to measure width/depth and mark on subflooring just where everything is going. Do you have room for the elongated toilet seat when opening the door? Things like this. I don't know how many times I was sent back to get the right item once the wrong one just didn't fit. Some distributors will charge a restock fee for returned items. Be warned. :)

Walls - taping, sealing, prime and paint/finish. This is when - after all is dry and looking wonderful - fans and lights too, are installed. Be sure as rain where they are to be placed. Once the hole is there in the ceiling...if it needs to be moved -- you will notice patching. Switch plates, etc. (might want to buy TWO of them, if one gets ruined)

Some say floor next. (Heating in floor?) I say install tub/toilet/sink. Run the water to be sure there is no leaking/sealing probs. More than one time a nice floor has been ruined due to leaks between the sub and the flooring. Then tile or whatever. Vanity can be placed on top of flooring and probably should if you decide to change from vanity to pedestal type later. Unless you rip out the old flooring and start over...
your choice.

Then light fixtures. Once all the huge hammers, ladders, etc have been removed :) Broke a glass to a lamp during install that could not be returned or replaced due to it being on clearance. Had to change out the entire light fixture :(. Still sad about that but it looks ok.

Hope all goes well and you have no uh-ohs at all that can't be cared for quickly. Getting ready to do a tiny reno on my upstairs bath too after the estimates from local companies went way over budget. OUCH! Glad the one downstairs is done but that light fixture!! ;)

Remember, perhaps to buy 2 of some items, in the off chance something breaks during install. Just a suggestion. Video for later. Always fun to watch once it is done. Have fun! :)