Bro they won't be monitored. No fucking way.
They'll send you into a bathroom and probly put coloring in the toilet water and somehow disable the sink.
Get hand warmers from Sports Authority or other outdoor apparel shop.
The hand warmers will have the MAX temp in the fine print. The ones I used were 110 max. I used two of them, and they (conveniently!) had a sticky surface on them. Stuck them right to the 5 hour energy bottle!
Also, I brought a digital thermometer with me so I could verify it was the right temp. DON"T put that shit in your pocket! I used 2 giant hair ties (like the ones chicks use to hold their hair back when they wash it) around my thigh. This way theres no tape and the risk of them hearing the crinkling of packing tape when you remove it.
IF it's NOT the right temp, just dip the thing in the toilet till it cools. Also, don't verify the temp until you pour it into the specimen vial. It'll lose temp tranfering from one container to the other.
Finally, you want the temp to be around 90. That's about perfect. It cannot be above 100, and below like 80 is a fail as well I believe (may be different at differnt places)
Now, if you have a place that actually watches you, like for probation or something, you are in trouble. The only way I know around that is some very crafty plumbing with a bag of piss at your waist, a valve taped to the underside of your nuts, and aquarium tubing connecting it all and taped to the underside of your dick. you hold your dick with one hand and the other is next to it flicking the valve under your nutsack. Even then, you must run SEVERAL test runs beforehand to make sure you have a solid system (ie no leaks!) and can access all the components properly without them coming off or being exposed. That's no joke right there.
good luck. I'm happy to give advice if you have anything specific you'd like to ask.