Find work you're passionate about and you will do it well.
Eye contact. When you speak to someone, look them in their eyes. Work bullies are always looking for a sign of weakness. Look them in their eyes, say what you mean and mean what you say. Don't cower in the presence of the known @#%holes.
Be proactive. If you foresee something being problematic, have a solution ready.
Posture is underrated. Walk with a purpose. Stand like you are somebody.
Don't flirt and don't entertain flirting. That is, if you want to be taken seriously.
Know your stuff. The moment you realize you don't know something, learn it and know it for the next time.
Be human. Everyone I work with knows I love basketball. They know I'm married with three kids and a dog. I cry when we lose someone. I don't hide and cry, I let the tears fall. I never saw people cry and it made me feel weird when I bawled after my first very long and unsuccessful code. Now I let the doctors and nurses I work with see it. I know it means I'm human. I'm prudent and know my craft but I'm human. Coming to work with a guard up all the time looks and feels defensive. Defensive people often have something to hide. It makes you suspect. Hurting people and getting hurt is part of life. You can't protect yourself from it no matter how hard you try.