Find an anime that mirrors your interests in other non anime shows is my best advice. I disagree that you have to start with a "core" set of all the "traditional ones" that some people state but they're definitely a good place to start. The suggestion above for FMA Brotherhood is a really good one.
Some other short favorites of mine so you don't feel you have to watch a FULL series of 100s of episodes? Baccano! and Death Parade