I have liquid, powder, and a combo of the 2 makeup....best way to apply?

Ok, I have been using CoverGirl makeup for the past two years because I like it the best. I have TruBlend Minerals (powder), 'Clean Makeup' (liquids), and Ultimate Finish (liquid powder). For the longest time I used just ultimate finish, because it provided a clean look. However, when I started breaking out more it didn't work as well, so over the summer I got TruBlend and started using that on top of the other. At first I got 420, but that was way too dark. Then I moved to 415. Then to 410. And finally to 405, the lightest it goes, even though it's still a little too dark. The two together work well too cover up blemishes, but it's very heavy. So today I got liquid makeup and plan to use that instead of the liquid-powder one as my foundation. So, my question is, what combination should I use? The liquid then powder or the combo then powder? And how can I apply it so it looks as natural as possible while still covering up my blemishes on my forehead and occasionally other places? And why did I just type a life story and not ust get to the point?