Palm-rubbing wasn’t the only error Serafino corrected. Most guys she sees don’t realize that you should start working the product into your hair at the back of your head, not the front.

“What happens when you go to the front, the hairline is here, immediately this hair becomes too weighted, too greasy, too oily,” she said. Particularly for guys whose hair is receding, most of the hair is at the back of the head. “So we start with the back first, and then what’s left in my hands is the right amount, so then I can come in through the front and create texture.”

The advice should be helpful to plenty of guys. The men’s grooming market is a booming business, worth tens of billions annually. So it’s worth figuring out how to properly use all this stuff we’re buying.

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