There is a good bit of talk about toes down, float fore and aft positioning or other postures for the foot while pedaling. My feet are generally level while pedaling. I am also clipless. There are several pieces of advice which I have found useful.
Keep RPM (cadence) as high as you can (80-90 is good). Raise & lower your gearing to allow for a steady pace.
Practice working a smooth full circle during pedaling. One legged pedaling exercises can help with this.
As your foot crosses the top and bottom extremes of your pedal stroke, the motion should mimic the touch and feel of scraping a soft mess (mud or dog doo) off the bottom of your shoe.
The best advice though is make sure you are as comfortable as possible in your fit on the bike, making small incremental adjustments as necessary and ride, ride, ride.
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Just Peddlin' Around