One.

Heels. As a woman of 5'4, if you want to be taken seriously, wear heels. I've gone from 2.5 inches to 3 inches and it makes a difference. You walk with your chin up and share the height space with most others.

You also  can't dress like a bum  in heels, so you have do dress up a little bit. Being dressed up professionally gets you taken seriously.

Two.

For someone who will probably never being extremely hard on self, it's quite a realization to know that ones perception of self, and how you carry yourself, speaks way more than ones accomplishments. Accomplishments are only important in that narrow time range when they are being tested. For the rest of the time, you must be seen as deserving of success to be successful.