SUBSTITUTION: Tips, tricks and guidelines by N2 Invest a few bucks in a human digital thermometer. They are fast and accurate. I cannot over emphasize the importance of PRACTICE, PRACTICE, and PRACTICE!!! If you use condoms, be sure you use NON-lubricated condoms and rinse the condom to remove the powder from it. You can also use a well rinsed, 2 oz shampoo bottle (travel size). Now that you have your digital thermo and condoms/shampoo bottle, start practicing by filling your chosen container with 105 degree water. If using a condom, fold the loaded condom over the tip of the digital thermo to take its temp. If using a plastic bottle, place the tip of the thermometer directly into the water. Place the bottle/condom in your crotch. (Two pair of tighty whity’s holds it in place better and adds extra insulation to maintain the temp) In my experience, I find the water/pee container crotched inside your briefs, cools at a rate of about 1 degree every 2-3 minutes until it stabilizes at about 94-98 degrees. DO NOT plan on using toilet/bathroom water to cool it down. Most testing joints color their toilet water blue to foil using it, and if they hear you turn on the sink water or flush the john before you give them your sample, they may require you to re-submit or fail you. If your sample is to warm when you get it in the cup, simply swish it around in the cup while you blow on it. You can cool it at a rate of about 1 degree every 30 seconds, but don't over do it. PRACTICE! You can't re-warm it at that point. In the reverse, I find I can warm a substitute urine product from my pocket temp of 85-88 to 96-98 in about 20 minutes with body heat by crotching the container. The test cup temp strip is attached to the cup just like they are stuck to the side of a fish aquarium. The temp strip will read from 90-100 (some non-DOT require 94-100) so you can see your pee temp and cool it if necessary before you give it to the collector. One more tip. If you are using a condom, I don't tie the end of the condom. It is too risky in my humble opinion (IMHO) to try to puncture it to get your pee out. I take the condom with my 2+ ounces of pee in it and give it a spin, like you would a bread bag. Then double it over itself and use a wire tie (trash bag/bread bag type tie) with the ends rolled over them selves (to prevent puncture) and twist it tight to close the condom. To empty your condom, simply untwist the wire tie and let the condom untwist. Then place the open end of the condom in the cup and empty it. Check the temp on the side of the cup, and give it to the collector. Once again let me say PRACTICE. Practice carrying it in your crotch, practice emptying it into the cup, etc, just practice. Men: IMHO the best place/way to crotch and carry the 2oz shampoo bottle/condom is to place it between your scrotum and anus. If you have any question as to where this spot is, stand up with your feet shoulder width apart. Reach down with your hand and cup your testicals. Note where your bird and ring fingers are touching. That is where you want to carry the bottle. It this position I find you can carry on about your activities normally while maintaining a 94-95 degree sample temp. To raise the sample temp to 97-98, simply sit down and cross you legs so that the container is enclosed between your thighs. It about 10-15 minutes the sample will warm to body temp, 97-98. Women: You can of course carry a substitute sample the same as the men, but post by females write that it is also easy to carry the bottle inside your vaginal cavity, where it will maintain a 98 degree sample temp or you can use two 1oz bottles and place one under each breast, held in place with a well padded bra for added insulation in maintaining the temp. Please remember that these suggestions are just guidelines and may need to be slightly modified to suit your particular need and comfort. The key to successfully substituting is to PRACTICE.