Hi,
I wouldn't buy that thermometer as it doesn't read humidity.
Irritatingly I can't find the one on the walmart site that we normally suggest.
There is this one but it is double the price.
This is what the one we like looks like;
I got the pic from Agentra's most excellent post here.
The normal light cycle of the room should be enough for the snake to get a night and day routine so I wouldn't bnother about that - plus turning the light on and off tends to mean a dip in temperatures which you do not need unless you are conditioning for breeding.
If you need the light to supply heat the best bet is to use either a red or moonglow bulb and leave it on 24/7.
I have never used the towel and can see the use of it as a cooling device but you need to be really obsessive to make sure it doesn't end up as a breeding ground for bactieria. You don't really need to worry about that when using something like foil or perspex. But obviously you wont get the cooling effect at that point.
It all depends what your humidity is actually like when measured in different spots around the tank with a good digital gague.
The reason we suggest the aquarium backing is it looks nice when viewing the inside of the tank which means you can put on insulation to the outside of the tank over it if you have trouble reaching the needed temps - it also makes the temps a little more stable.
Most of the problems people have with glass tanks are fluctuating/ too low temperatures and low humidity and all these little tips tend to make things a little easier.
Once you get the good thermometer though you need to measure the temps directly on top of the UTH as they can get warm enough to burn the snake if not controlled by a rheostat or thermostat.
There was information about those in Agentra's post too.
dr del