Its not very difficult...just remove the shield beneath the radiator and loosen the drain plug with a screwdriver. Refill with water and cleaner if needed and drive for about 15 minutes. Repeat the process using only water several times to flush out all of the old coolant/cleaner, or until the drained stuff is clear.
Refill with about 1.5 gallons of any major brand coolant.
Also, you may want to use distilled water for that last flush since there is no hardness in the water.
