The purpose of a humidor is to preserve the freshness of the tobacco leaves by regulating the ambient humidity to maintain the cigar's form and proper taste. A dry cigar will burn too hot and cause an unpleasant smoking experience. Too much humidity can lead to mold or other problems.
However, many casual smokers and people who purchase cigars only occasionally may not need to invest in a humidor. Fortunately, you may already have everything you need to adequately preserve your cigars.
Find a household container that has a tight seal, although hermetic seals are not necessary. The container should have enough space to store the cigars and a sponge. If you plan to store your cigars long-term; keep a hygrometer in the container. Remember that the sponge must never come into direct contact with a cigar, or the tobacco will form mildew. Because it’s perfectly safe to store cigars laying flat or standing up, coffee cans that have been thoroughly cleaned to remove the smell of coffee make great cigar containers. However, if you will be traveling with the stored cigars, a food container with separate compartments to prevent the cigars from rolling onto the sponge is preferred.
Purchase a sponge specifically manufactured for humidors, since they are designed to prevent the cigars from becoming excessively moist. Humidor sponges can be purchased at most cigar shops, and must be used with distilled water or a special propylene glycol solution. Alternative hydration systems such as polymer crystals are slightly more costly, but significantly more convenient. A household sponge cut to a square about 1.5 inches on a side can be employed for short-term storage, but only if it is brand-new. Never attempt to hydrate a cigar with a used sponge. If you use a household sponge, dampen it with purified (preferably distilled) water, and wring out as much excess water as possible.
Purchase a hygrometer if your cigars are being stored long-term to ensure that they remain at a proper humidity of 68 to 74 percent. Most cigar shops sell analog hygrometers for less than $10, although these require calibration. Digital hygrometers do not require calibration, so may be worth the extra money.
Check the humidity once a day initially to make sure that correct humidity is established and that the sponge remains moist. Gently squeeze the cigar wrapper to make sure it has not become brittle. Once you are comfortable that your storage system is configured properly, you can gradually check it less often depending on the relative size of the sponge and the container.
Open and inspect the storage system at least once every two weeks to give the cigars a regular supply of fresh air.
If your cigar came with a cellophane wrapper, keep the wrapper intact to help preserve the cigar's moisture. A cigar which has dried out and become brittle may be saved by being stored at a higher level of humidity for several days. While the recommended humidity level for cigars is 68 to 74 percent, many smokers have specific preferences at the high or low end of that range as a matter of personal taste. Some smokers enjoy their cigars stored at up to 78 percent humidity. Cigars can safely be stored as low as 65 percent humidity for long-term storage.