Mealworms are easy. Let some pupate and come out as beetles and then put those beetles in a flat storage tub (I think I'm using 12 qt storage tubs but I'd have to go look at the label to confirm for sure). Put an inch or so of substrate.If you check around you can find recipes for dry cricket or roach food here on the forums and that is a great way to go. You can also use oatmeal or wheat bran but the worms will not be nearly as nutritious as if you use a "gutload" as for crickets or roaches. I grind the ingredients in a coffee grinder to the consistency of flour. This is unnecessary if you only need a few dozen worms at a time, but if you feed hundreds at a time like I do, it makes collecting the worms easier as you can sift them with a wire strainer from the substrate. On top of this I put a paper towel- this is mainly for the beetles which have a hard time flipping themselves in the flour substrate if they happen to find themselves upside down. They also like to cling to it, and I change them into a new tub each week to make more eggs, so it makes collecting and moving them easier. Also the worms tend to "surface" on top of the substrate beneath the paper towel, so it makes collecting them easier if you only need a few at a time- just lift the paper towel and pick them off the surface of the substrate. I have many beetles and each tub this size can hold many thousands of worms very easily (I started once with 10,000 worms in a tub this size- maybe even more can live in one). If you are only feeding a couple of chameleons you can just keep everything in the same tub, maybe switching the beetles as you find them to a new tub a couple of times a year so you can eventually feed one tub out and clean it and then rotate again. If you are feeding many lizards, or want to sell the worms to other chameleon keepers, you can rotate the beetles each week as I do. Soon you will have 18 tubs give or take a few, filled with all sizes and many thousands of mealworms that can be fed to anything from hatchling to adult chameleons. When one tub is fed or sold out you can clean it and set it up again for the beetles the next week and just keep rotating through. The tubs are best kept at about 80 degrees. I use a 12" heat tape on a thermostatic controller (herpstat by spyder robotics) on a long shelf for my tubs.
Crickets are easy too. Get large clear smooth sided storage tubs that they cannot climb out- the largest you can find. For me this is 30 gallons. Put your crickets in there. I rough the walls and floor of the tub up with course sandpaper so the crickets can have traction on the floor and climb up the walls about 3/4 of the way- gives them more surface area and makes collecting them easy to feed. Start with 500 or 1000 adult crickets. They need heat also- Somewhere in the mid 80s works best for me. The more heat the faster they grow (and age) but the faster they dehydrate also. I set my heat tape for 87 degrees on my cricket shelves and that has worked best for me- you may need to experiment a little. To reproduce them, take a shallow food storage container (sandwich box kind of thing- mine are maybe 10" long and about half as wide and a couple of inches deep), fill with damp substrate- I use vermiculite and add water 4x the weight of the vermiculite. You can use other damp substrates- some simply use dirt or sand and I've had crickets breed in mulch before also. Put this in the box with the crickets at a location where the crickets can easily get in and out of it. In 24 hours it will be loaded with eggs. Remove the container, put the lid on it, and place it in an incubator at 84 degrees. About a week and a half later you will have zillions of little pinhead crickets in the container. Move them to the same sort of box you have the adults in. The trick with pinheads is giving them plenty of moisture in a way they can get at it. In hawaii you probably can find lots of rotting fruit that will work well- not moldy, just soft, very ripe fruit would be the thing. You can make more pinheads every day this way.
Honestly, if I were in a tropical climate though, and only needed to feed a few chameleons, I'd probably make a large terrariums outdoors. I'd take galvanized steel roofing and make a frame about 3'x3' that sunk into the ground about 18-24" and continued above ground about 18" to keep things like rodents out, and then on top of this base I'd make a cage out of rubber coated hardware cloth that was about 4 or 5' high on top of that base. The hardware cloth would allow insects into the cage. Then I'd plant flowering bushes in the cages to attract local insects such as bees and flies.
Lastly, don't forget these guys. They are good food for chameleons:
http://naturalfarminghawaii.net/2013/03/dr-jeff-tomberlin-on-black-soldier-flies/
