Advice needed on how to perform yoga correctly?

I'm really into healthy, tranquil living, and would really like to take up yoga. Where is the best place to do it? What time is best? Do certain measures need to be taken? Any sites with video's e.t.c are also very helpful.Advice needed on how to perform yoga correctly?
You just need to go slowly with your yoga practice.. learn and apply. the beauty is that yoga doesn't entail much time from you, and the results still amazing! for references, this free yoga e-course is very awesome and useful for you: http://www.yoga-health-beauty-energy.comAdvice needed on how to perform yoga correctly?
I do a form of power yoga called YRG. The best time for me to do it is in the morning. But I guess it depends on your lifestyle as to when you can make the time. My back feels so much better!