I first used the Google traffic estimator to build my Pay Per click campaign with google adwords and based on the estimator, I was going to get positions 1-4. However, after running the campaign, my ads won't simply show. I don't understand why. When I check some of my keywords, SOME of my keywords have this message:

Bid is below first page bid estimate of $0.70

The amount varies depending on keyword but that same message appears on about 7 of my 12 keywords. I wonder if my ads wll not run until that message dissapears from my keywords? What exactly do I need to do for my ads to start appearing?