Depending on where I've lived I have used drippers, hand sprayers, ultrasonic humidifiers, auto misting systems or combinations of them. I've found that each cham has a preference and they can be very stubborn about changing their little minds. I found drippers a pain to manage and now don't use them. What I have learned is that a healthy, well-hydrated cham who has the correct level of overall humidity simply doesn't drink a lot every day so you can easily miss it. These days here's what I do:
Check the cham:
Check urates whenever possible. If they are white, the cham is doing well. Check the cham for signs of dehydration...skin tenting, trouble shedding, sunken eyes and casque, papery skin. Offer fleshy foods like silkworms and hornworms and feed all insects a good diet of fresh greens and fruit.
Check the cage:
Keep track of the cage humidity with a quality digital gauge. It can change dramatically with season. You can sort of predict how much your cham will need to drink or how fast it will dehydrate. The more lights you use the drier it will tend to be even if the temp is OK.
Create a mini rainforest:
I really fill my cages with live plants so I can hardly find the cham. Most of them prefer this anyway. If the cage tends to be too dry I hang clear showercurtains on back and sides to hold in moisture and provide more surfaces for evaporation. Fog and/or mist using timer controlled misters or humidifiers. I don't have to be home to create cycles of wetter and drier air during the day.
Experiment with different ways to offer water. I've found I can "train" my chams to accept water pretty directly by first misting the cage foliage with warm water (not the cham) until I see the cham start reflexive swallowing and licking its lips. When they start this I slowly drip warm water on their head from above letting it run down their face. Most of them will start licking the water as it channels down their casque and face. I keep this up until the cham tips its head straight up (a sign they are getting full) and turns away from the water. Once they know what this is all about I can do this pretty quickly if I give the right "cues". I've even had a cham who would start licking water out of my cupped hand which was pretty cool.
If the cage air is dry the cham will dehydrate through respiration even if it can drink regularly. So, I use humidifiers and misters even though the cham may not drink from droplets forming on the plants. They are really used to hydrate the air, not direct drinking.