You could try taking a class, but to really master all the nuances, hang out with yiddish speakers. Pick the dialect that best fits your background, and give it 6 months.
Let me give you the 1st line to get you started. Ask someone; Vus iz neis? (which means whats new?)
But be sure to pronouce it: vus e’nayies, so they know what you’re talking about.