Spare tire/wheel

Do make sure you chock the diagonally opposite wheel. Do take care to not get yourself underneath the RV when it is supported only by the jack. (I sometimes need to be partly underneath to jack up the rear axle, but the wheels are attached to the hub at that point sufficiently that, should the jack slip, they would keep the motorhome from crushing my body. The lug nuts should only be broken free before jacking, not removed to any great extent.)

Good advice!
Carrying and using a jackstand should be in every person's suite of tools for tire changing and working underneath. Jackstands have saved many lives and the price is cheap. I just used one, today, changing oil in the Wife's car. I make it a point to use one every time I'm underneath a vehicle. My family doesn't need a statistic.