Analog hydrometers may be calibrated in two ways:
The usually suggested and most exact calibration technique is to put the hygrometer coupled with salt solution inside a plastic box of small proportions. A small quantity of salt needs to be taken and moistened such that it remains damp but does not dissolve. The hygrometer and salt should then be placed in a sealed plastic box. At the end of 8 hours humidity of the box should be 75 %. Needle of the hygrometer maybe adjusted with a screwdriver, at the rear, to mark 75 % humidity.
On the other hand, you might get rid of the hygrometer from the humidor, drape the hygrometer in a carefully damp cloth, and after about an hour regulate the hygrometer on the back with a screwdriver to about 96 % relative humidity.
The humidifier must be placed on a plate and moisturized it with propylene glycol solution( applicable for a sponge-based humidifier) or distilled water.
Humidifier is left in the solution for about an hour and it absorbs liquid. Once it has absorbed an appropriate amount, the humidifier needs to be shaken in order to ensure that the liquid that was not riveted would be eliminated. The next step is to make dry the humidifier with a piece of cloth.
A cloth placed in distilled water should be used to wipe the walls of the interior of the humidor, divider and trays.
A glass of distilled water is placed in the humidor for three days. If you heat the water in a microwave before placing it into the humidor then the process takes only about a day before the humidor starts functioning. Basically the walls of the interior must absorb enough humidity.
A humidor that is well filled ideally must be aerated at the least about once every two weeks to supply it with fresh air on a regular basis. Temperature ranging between 64-70 ° F( 18-21 ° C) is deemed perfect.
Temperatures veering beneath 54 ° F( 12 ° C) may cause the aging process of the cigars to be seriously damaged. Thus it is only up to a point that cold wine cellars can serve for the purpose of cigar storage.