I recently left my position leading a large team of bright, talented, witty, and compassionate genetic counselors. The past 3 years have been some of my most enjoyable professional years as I have learned how to grow as a leader while staying committed to my mission of providing optimal patient care in the context of genetic counseling. Below is a highlight of some of the top lessons I've walked away with.

Take the time to hire well. Your job is easier if you have the right people in the right role. And once you have the right people in the right role, let them be part of major decisions that impact the team.
Let your people shine. Recognize team members' strengths and accordingly assign projects that will let them shine. Your success as a leader is directly correlated to how successful your team is- invest the time to help them be successful and confident in their roles.
Start everyone off with trust until they give you a reason to not trust them. If you have done a good job hiring, know that you are bringing on competent, talented people. My team knows that I am famous for the saying, "I don't care when the work gets done, as long as it gets done". When your employees know that leadership values them as not only employees, but individuals with families and lives, they will give so much more back to the organization.
Listen, really listen to what your team is concerned about. Knowing that they're heard goes a long way even if you can't change things. Let's face it, if you're a leader of a large team, chances are you're going to have to make some decisions that may not please everyone. And that's ok- your job isn't to please everyone, but knowing that your team feels heard can go a long way.
Don't be afraid to not have all the answers. Honesty, while sometimes frustrating, is appreciated. You can lead with confidence without having all the answers. It's how you tackle the next steps that define you as a leader.
Have meaningful 1:1 meetings where you really get to know your employees and the work that they are doing. This will equip you with knowing who best to delegate tasks to (this is key for the success of #7 below!).
Learn to let go of taking the lead on certain projects (even the ones you may be most passionate about!). Trusting your teammates with tasks and projects is essential to free up your bandwidth so that you can focus on the bigger picture and be present for your team without feeling like you are always caught in the weeds.

In genetic counseling, we learn so much about the importance of listening, communication, and empathy. These are the probably the most valued skills that translate directly into successful leadership. I send a heartfelt thanks to all those I worked with who helped shape me as a leader and took a chance on many of the "out of the box" ideas I'd propose.