Be a leader to everyone you work with

You should show leadership to your juniors. You should show leadership to people at the same level as you. And you should show leadership to your bosses. 

It doesn’t matter where you sit in the hierarchy. 
It doesn’t matter how extroverted you are. 
It doesn’t matter how confident you feel.

Leadership is getting people to perform to the best of their abilities while driving towards a shared goal. 

You can – and should – get others to be their best using whatever methods work best for you.