Welcome to the world of chameleons and to the forum!
First of all here is some important information to know when you are keeping a chameleon...
Exposure to proper UVB, appropriate temperatures, supplements, a supply of well-fed/gutloaded insects, water and an appropriate cage set-up are all important for the well-being of your chameleon.
Appropriate cage temperatures aid in digestion and thus play a part indirectly in nutrient absorption. Temperatures needed can vary with the species and age. For hatchling panthers I keep the temperature in the warmest area in the low 80's. For older panthers I keep it in the mid to high 80's for the most part.
Exposure to UVB from either direct sunlight or a proper UVB light allows the chameleon to produce D3 so that it can use the calcium in its system to make/keep the bones strong and be used in other systems in the chameleon as well. The UVB should not pass through glass or plastic no matter whether its from the sun or the UVB light. The most often recommended UVB light is the long linear fluorescent Repti-sun 5.0 tube light. Some of the compacts, spirals and tube lights have caused health issues, but so far there have been no bad reports against this one.
Since many of the feeder insects have a poor ratio of calcium to phosphorus in them, its important to dust the insects just before you feed them to the chameleon at most feedings with a phos.-free calcium powder to help make up for it. (I use Rep-cal phosphorus-free calcium).
If you also dust twice a month with a phos.-free calcium/D3 powder it will ensure that your chameleon gets some D3 without overdoing it. It leaves the chameleon to produce the rest of what it needs through its exposure to the UVB light. D3 from supplements can build up in the system but D3 produced from exposure to UVB shouldn't as long as the chameleon can move in and out of it. (I use Rep-cal phos.-free calcium/D3).
Dusting twice a month as well with a vitamin powder that contains a beta carotene (prOformed) source of vitamin A will ensure that the chameleon gets some vitamins without the danger of overdosing the vitamin A. PrEformed sources of vitamin A can build up in the system and may prevent the D3 from doing its job and push the chameleon towards MBD. However, there is controversy as to whether all/any chameleons can convert the beta carotene and so some people give some prEformed vitamin A once in a while. (I use herptivite.)
Gutloading/feeding the insects well helps to provide what the chameleon needs. I gutload crickets, roaches, locusts, superworms, etc. with an assortment of greens (dandelions, kale, collards, endive, escarole, mustard greens, etc.) and veggies (carrots, squash, sweet potato, sweet red pepper, zucchini, etc.)
Calcium, phos., D3 and vitamin A are important players in bone health and other systems in the chameleon (muscles, etc.) and they need to be in balance. When trying to balance them, you need to look at the supplements, what you feed the insects and what you feed the chameleon.
Here are some good sites for you to read...
http://chameleonnews.com/07FebWheelock.html
http://web.archive.org/web/200605020...Vitamin.A.html
http://web.archive.org/web/200406080...d.Calcium.html
http://www.uvguide.co.uk/
http://raisingkittytheveiledchameleon.blogspot.com/
http://web.archive.org/web/200601140...ww.adcham.com/
If you can't access the sites above that have the word "archive" in you can do it through the WayBackMachine.
The above has given you information on the supplements, lighting and gutloading....here is some information about your set-up...
you can use a screen cage or one of the glass ones that has a screen lid and some vents in the front. I have always kept my Senegals in the glass ones and they have done quite well there. There are different issues with each. With a screen cage you will have more difficulty keeping it humid, keeping the temperatures right in the cage, preventing the misting from going outside the cage and damaging the wall, etc. With a glass on you need to make sure that you don't let water lay stagnant on the floor of the cage and that you set your lights up so that they create a chimney affect to help with the air flow. The humidity will be easier to keep up, but you will have to make sure that don't let condensation form on the sides of the cage. If you live in a hot area, then screen is best. If you live in a cool/cold area then the glass may be best.
For an adult Senegal, I would recommend a cage that is at least 18" x 18" x 24" high. Make sure that there are lots of vines/branches for it to climb on and enough non-toxic well-washed (both sides of the leaves) foliage to make it feel secure.
Water can be provided by misting, using a dripper at least once a day. Senegals need quite a bit of water.
Regarding using WC insects...there can be a risk of parasites and you must be careful to collect them in areas where there are no pesticides, etc. used...and where the plants they might have eaten are not toxic.
Hope this helps.