First things first there is not just one way. You are free to put the tracks that you want in it depending on what you want people to use/do.
What seems mandatory is of course wet/dry vocals if there is vocals. also if you have adlibs and such things you may wanna have these on separate track and not just have all your vocals on the same killing the flexibility.
You may or may not put your drums tracks but the kick is cool to put so remixers just have the tempo right away.
For the instruments having them dry is good aswell so we can mix it better with our own instruments.
finally everything under 0 dB, no panning and only the effects necessary to the sound are of course a MUST.