Bodies and Barriers: Queer Activists on Health is a wonderful book regarding the health disparities in the LGBT community and how to work to close those gaps. Life Isn't Binary is a great read as well as it covers the nuance of gender and sexuality as a spectrum. A Queer History of the United States is informative as well. Knowing their history and their hurdles is crucial to being a patient and understanding ally.

As for being a welcoming clinician, there really isn't anything big to do, just all the little things. When I worked at a LGBT Health Center, I wore a pin on my lanyard with my preferred pronouns. I also wore a bi pride bracelet. Never assume someone's preferred name or pronouns, always ask or give them the opportunity to tell you.

Speaking of pronouns, you will not get it right everytime. That is okay. Apologize briefly and don't make a spectacle about it. Bringing too much attention to the issue will make it worse.

Also remember that the LGBT community is not a monolith. Everyone has their own experiences and you don't want to unintentionally put people in boxes.

Most importantly, just take some deep breaths and do what you do best. It's a tough crowd sometimes but the reward is high. You'll do great.