Over the course of my career as a lawyer, I have realized that if you want to be recognized as someone with authority, you have to show up and look like it.
Take a look at the image above and ask yourself which one of these women is the boss and which is the assistant. Even if you didn’t know that the woman on the left is Amal Clooney, it’s pretty obvious that she’s the boss. In contrast to Clooney’s smart looking dress and accessories, the woman on the right is wearing leggings and a sloppy looking top. Which is fine if you want people to see you as the flunky.
Dressing for work allows you to command respect before you even say anything. Think of Kamala Harris in the white suit she wore when delivering her first speech as Vice President-elect. Was there any question of her power and position? No. She impressed even as she walked up to the podium.
So if you want people to take you seriously (and promote you), you need to dress. If you want to be treated like the boss, you have to look like the boss.