Hi Nami,

Your best bet would be to tile the floor first ( this saves a lot of time cutting around toilet etc) Then you will have to install the bath first before gyprock, Then you can tile all walls. Once finished you can install toilet and vanity.
It really depends on how soon you want a working toilet and vanity? but if you can hold out untill all wall tiles are layed, i would do it that way.Hope that helps.