I found the best way to rack up points is to:
1. Start the game on expert (so your speed will be 20)
2. Get as many ghosts to follow you. You'll have to "wake up" many of them and go out of your way to do so, but it will be well worth it once you get to the power pellet.
The other method is to try to get as much fruit and clear out all the mazes you can, while getting ghosts in clusters. I found this method is much tougher, and doesn't leave much room for error. I like the first method better, personally.