I have discovered the fastest way to lose at this game.
Your score will be about 500 points using this method, give or take 100 points.
You go up as much as you can until you can't go up anymore. Then you go left as much as you can, until you can't go left anymore. Do the same with the down direction. Repeat with the right direction. Repeat the whole thing over and over again.
Boom. Super low score. I got 332 once. Beat that!