Go buy some athletic shorts from walmart (I wear two pairs when i've gone in to make sure it wont fall out accidentally). Wear them and you can place your small container on the inside of your thigh, or if you please, further into the depths of your gooch. This will help keep the urine at the correct temperature (or you can also buy hand warmers and put them in your pants, as well)
The 2 main things you need to focus on are: 1) Having enough urine and 2) the temperature of the urine. If either of these two things does not fulfill their qualifications, they will require an entirely new sample from you.
(LONG STORY) I've had the unfortunate experience of not having my urine at the correct temperature...I had a friend piss clean for me and kept it in the fridge overnight, got entirely too stoned the next morning before going to do the test (bad fucking idea). And ended up trippin out about the urine being cold, so I heated it up in the microwave and didn't let it cool down to the correct temperature, it was just barely too hot. JUST FUCKING BARELY. This was for my conversion of my job (i was temporarily a contract employee and was being hired on full time).
I had already cheated on the original test (about 3 months earlier) so I didn't think about having issues...Got to the lab, did the test, brought out the cup for her...and she literally just tossed it in the trash and demanded a new sample from me. This is where it gets weird because I remember looking at the temperature strip before I poured it out, and it was right where it needed to be. But she claimed it wasn't and threw it away with no second opinion. I was told that if I left (which was really my only choice because I would have pissed hot as hell, i smoke dabs every day) they would contact my employer and let them know that I refused to take a second test. I said fuck it, and peaced out.
I saw it as either: I pissed again and would show up hot for marijuana, and not get the full time employment...OR leave and try and convince my employer of something, so that I could re-take the test.
Got to work and basically explained to my boss that the lady at the lab made me feel like a complete criminal, and was forcing me to give another sample. I explained that i've never felt that way before, and felt like I was being "backed into a corner" ....if you will.
I don't know whether my story was convincing enough, or whether my boss just really likes me....Because i'm still at the job to this day. I was extremely stressed out, as you can imagine, after all this happening, so I asked my boss if I could head home for the day...So obliged. I got a call from the recruiter about an hour later asking if I could "take the test in 30 or so." Man I fucking lucked out...