When a professional (especially a lawyer), rather than looking for a job, just goes and finds clients. This takes guts and a willingness to work constantly for precious little money in exchange for autonomy.
Law student 1: Hey, you made top 10%. I bet you could get that $160,000 opening at Rob, Ewe, and Howe!

Law student 2: Fuck those guys. I don't want to kiss ass for the next 20 years. I'm hanging out my shingle.
by cogitheum@mac.com February 7, 2009
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Verb phrase. To start a business.

This refers to old shops or guilds in the 1800's and before, where their business name was carved on a piece of wood called a shingle, which they would hang out over their front door for pedestrians to see.
"Your sister graduated Law School last week? When will she hang out a shingle?"
by June 16, 2021
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