Mind games: Getting in people's heads, learning how they think, react, move. Know what makes them agitated and exploit that to make them slip up then go for the kill.
Be unpredictable: Change officer load outs often. If knowledge is power, then being unknown is like being invincible.
Killer instinct: Chase down runners with aggression. Ram them.
I'm starting to sound like the Book of Five Rings here, I read it twice a year for karate. It's a good read if you want to build a sense of competitiveness, for anything. Same with The Art of War, we really mean it when we say "Less QQ, more Sun Tzu".
Honestly, just two days ago I did pitiful damage in cap and holds, I figured it was because I was science so I concentrated on sneaking around the map, being a pest and forcing the Ks to come kill me to get their node back. Then one time I accidentally left my power setting to weapons (instead of shields, as my usual plan was to make them kill me slowly). One BoP decloaks, I make a show of firing at him... except this time I'm actually doing damage. His forward facing is going down fast. My fearful instincts take over and I steer away from him, and on a lark I decide to give him T:HY from my new aft quantums. A couple seconds later I'm treated to loud explosions and I look at my target. 6% hull. I position myself to strafe and my phasers finish the job.
Fed PVP Strategy 101, and it only took me a month to get it, lol. But that first real 1 on 1 kill gave me confidence to keep trying and refining my attacks, collecting truly useful boff powers, and now I almost always place in top 5 damage (even with me mainly avoiding battle and going for nodes), win the vast majority of my 1 on 1s, and if the Ks want to kick me off of a node they need to bring a few friends.
Moral of the story: Having fun losing is a foolproof path to having fun winning.