That's mostly correct, but there is no need to tighten them every 100 miles. It's generally advisable to check them after the first drive, some say after 500 miles. Once tight, the only way they will come loose on their own is if the hubs are mounted on the incorrect side, if the splines are very worn, or if the hub tapers are damaged.
They should be tightened in the air, not on the ground. Once you place weight on the wheel, you are placing a side load on the outer taper and this will create friction, which in turn reduces the ability of the nut to further spin on the hub threads. Some people believe that hitting the knockoff ears hard while in the air can damage the hub bearings. Others including myself do not believe that it is possible to do damage to a set of wheel bearings with a little 5-pound lead hammer. I've been doing it this way for 20 years with no ill effects to the bearings.
You don't want to over-tighten them anyway, because this can damage the inner hub taper. Hit the ear of the knockoff with good solid blows until the ear moves less than 1/4" after a hit. That's plenty tight enough. If you have problems keeping the wheel from spinning as you hammer, you can either lower the car just enough to touch the ground with the tire, or put your shoe between the tire and the ground to act as a wheel chock.
Removing the wheels is exactly the reverse of putting them on. Raise the car, hammer it loose and spin it off.