not too hard. I dried three of them, one rotted. When dried, washed them in hot soapy water, scrubbing with a rough sponge takes off the outer skin. Dried it again, about a day, then drilled some holes in the top. At that point I scrapped out the inside as best I could through the top, then used rocks, then gravel, then sand to clean out the inside. Picked up some corks, wrapped ihem in 150 grit sandpaper, used that to fit the corks. Penciled in the designs and used india ink and a small pain brush. When that was dry, I put them in a ~200 F oven and melted some bees wax. poured it on the inside, swished with the cork in and dumped it. Brushed bees wax on outside while still hot. Water still tastes a bit like gourd, but worked well. Each gourd cost ~$2.50 at the greenhouse. Corks cost me more than that. The twine was just sitting around.