You need:
1 cooler, 1 travel soap dish (try to get the kind with a flat top and bottom because then you can make 2 humidifiers from 1 dish), 1 block WET floral foam, propylene glycol, distilled water and cigars.
Cut a block of foam to about the size of a bar of soap. Put it into 1/2 of the soap dish. You don't need a lid. For the 1st use pour a 50/50 mixture of PG/distilled water over the foam until it's saturated.
After that just use DW to replenish it. Re-add the 50/50 mix every year or so.
Fill your cooler mostly with your boxed cigars. That way there's plenty of spanish cedar in there. I put loose cigars in old boxes when I have to. I leave the cooler's drain plug open so that some air can circulate. You may add a hygrometer if you want. That's it, you're done.