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The food and water they intake is what helps them molt. The moisture within the spider is released between the new and old exoskeleton and this is how they slide out. Being waterproof (the spider)...all other water is useless including air humidity. Watering one side of the enclosure preferably near the water dish is all that's needed. Spraying is often wasteful as it evaporates so fast it's not helpful at all.
I dribble a few drops of water down one side of the container where I can't fit a water bowl in. Some people use the blisters that tablets come in and another alternative for a small bowl is a small Lego brick.