The Chovos HaLvovos has a whole section devoted to how a Yid should choose his occupation. It’s in the Shaar HaBitochon.
I know someone who is a dental hygienist. Pay is excellent. Training is relatively short and inexpensive. You can choose and keep changing your hours (it’s easy to contract with different dentists for different hours). You are in high demand. You can work a lot or a little.