Respond to sarcasm with grace.
If you look young, it's inevitable that someone's going to comment on your appearance. "How old are you, anyway?" "Hey, are you a female 'Doogie Howser'?" "You don't look old enough to be in charge of a department."

Though it's tempting to respond emotionally to such inappropriate statements, resist the temptation. Don't make your young appearance a basis for conversation. After all, it's not relevant; your competence is.
Nothing is impossible for the motivated young woman. With a little forethought, you can put your best - and most mature - foot forward. By acting like a professional, you'll be treated like one; even if you get carded into your thirties.

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