Remove stone & saturate felt cushion with ink. Prime the stone by adding ink to only one side of the stone. Put stone back in container with the inked side facing the inked felt. Capillary action will force the ink to the surface of the stone. If not, add more ink to the felt only, NOT the stone. If the stone is over inked, blot excess from the stone surface with a clean, lint-free towel or cloth. Add ink to felt only when the impression becomes faint.
Note: After prolonged exposure to air, most solvent based inks will dry out in the pad. It is not necessary to add more ink with this occurs. Just add a few drops of ink thinner (solvent) to the surface of the stone to reactivate the dried ink. To keep ink in pad moist, keep cover closed whenever it is not being used. Overnight place the ink pad in a re-closable plastic bag.
NOT ALL INKS ARE FORMULATED FOR USE IN STONE PADS!
Avoid using heavily pigmented inks - most opaque colored inks are pigmented. Avoid certain types of black pigmented inks which can clog the pores in the stone pad. If you must use a thick, heavy, opaque ink - first apply the ink to the felt, then - apply small amounts of ink thinner to the stone, next - apply ink to the surface side of the stone. It will take a constant application of thinner & ink to the pad surface to get desired results. Although thick, heavily pigmented inks are hard to use - it is worth the extra effort because of the results the rigid surface will not allow the background of the stamp to print or clog up.