Need a license?

I have a friend who recently moved to the US from the Dominican Republic. In the Dominican Republic, she didn't need any licensing to install hair extensions and cut hair. I know to cut hair you have to be licensed, but to do hair extensions, do you need a license? Do any of you do the extension install only and then the customer has to get the cut from someone else? Maybe have a partnership with a local stylist. You do the extentions and then send them to the stylist to finish up? I'm just looking for ideas that can get my friend some income coming in. She is really good at extentions but is afraid of getting in trouble legally.