There IS a special tool for driving those onto the pot, but I used a small screwdriver, and a small wood block, as a mallet. Not for the faint of heart, or unsteady of hand, for the same reasons as bolly mentioned, but you can drive the nut off, by placing the tip of the SMALL screwdriver blade into the slot, and tapping gently, driving the nut counterclockwise, being careful to avoid losing your purchase in the slot. Once you have loosened the nut sufficiently, you can remove it, by hand.