First month using ovulation test. Info please??

This is going to be my first month using ovulation test. I took one yesterday, and it had a faint line on it, then I took one this morning, and the faint line is a little darker, but not nearly as dark as the control line. What does that mean? Secondly, do I take them at the same time everyday? And do I use fmu on these or do I wait till the afternoon, evening? What are the best ones to take? Any info would be great. Thanks ladies!