Celebrity Lessons in Selling

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Justin Bieber Know your audience.

Pulling in $53 million in 2010 alone, the 17-year-old hit maker is the richest teen in entertainment. Sure, his albums and this year's documentary, Never Say Never racked in a lot of dough, but not all of it. Bieber—or his business manager—has made several smart moves to release products catered to his No. 1 fans—pre-teen girls. His new fragrance, Someday, is well on its way to becoming the best-selling perfume of the year, and his One Less Lonely Girl line of nail polishes with Nicole by OPI sold a million bottles in two months. Get to know who your product's biggest fans are and always keep them in mind when making any decisions.