A lady always covers up. Photo: Humberto Carreno, startraksphoto.com | Amanda Schwab, Startraksphoto.com

Like the devil and angel on all of our fashionable shoulders, Mischa Barton and Beyoncé show us the dos and don'ts of wearing a mini dress.

Don't: Rocker-chic Barton exits her limo recklessly, giving the photographers a prime view of her Spanx.

Do: Caught in the same predicament, Beyoncé lends herself a hand to keep her lady parts covered as she traverses the red carpet.

What did we learn?

When exiting a car in a short skirt, scoot over to the door, swing your legs around (while keeping them together--key!) then lean forward onto your feet and stand.

Or, just don't wear a dress that's so micro. We're just sayin'.

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