Bron81, I'm no expert I only used them 1 month but I got pg that month, what I did was use them twice a day morning and afternoon (around 2pm is the best). The idea of using them twice a day is while the surge usually occurs in can occur anytime so testing twice you have more chance of catching it. Mind you I got a +ve in the arvo and not in the morning.

You are best not to drink for a couple of hours before testing. In terms of not going to the toilet I dont' know but I assume you are best to hold as well.

Good luck.