The techniques vary slightly aircraft to aircraft, and also based on what landing configuration you have. However, the general gist is to hold off the malfunctioning side from the runway for as long as possible, slowing the aircraft in the process, until forced to put it down on the deck. This minimizes the contact between the wings and/or fuselage with the ground.
The single greatest danger with these types of landings is the risk of fire. The friction between the runway surface and the aircraft is tremendous generating an enormous amount of heat. This is particularly problematic when you consider that the fuel is stored in the wings.
Fuel may be pumped to the opposite wing to counter-balance weight and move the fuel away to the fuselage with the highest possibility to have contact with the ground. This technique will shift weight away from the missing wheels and consequently reduce the possibility of fire.