rest pause is doing a set until failure and only taking a short break. In DC, you take about 12 deep breaths, which should be about 20-30 seconds. Then do another set until failure.
Warmup sets shouldn't really matter. You just do what you need to, to feel like you are ready to go all out on your one working set. Depending how heavy you go and what muscle group you are doing, your warmup sets will differ. I probably do at least 5 warmup sets for stuff like chest and squats or something. First getting the muscle and joints warm and getting blood in there, then the next few I start adding weight working my way up close to my working set weight. Those last warmups are mainly to stimulate my muscles and get my CNS prepared to fire on such heavy weight. None of your warmup sets should be taxing on your muscles; you should not be getting any fatigue. When you are physically and mentally ready, then you give it your all and attack that one working set.
here are some good resources
Complete forum dedicated to DC, created by the founder:
http://intensemuscle.com/
http://dc-training.blogspot.com/