I'm amazed at the number of fishermen I see trolling who just sit there with their pole held out perpendicular to the boat. In my experience, you get a LOT more action with the sweep and pause technique. If anyone here is unfamiliar with it, here's how it works:
Keeping your pole parallel to the water, you sweep it forward (you should feel the lure action vibrate your rod tip), then (keeping the line tight), slowly move the pole back, usually a little bit more than perpendicular towards the back of the boat. Pause a second, then sweep it again.
What happens is, a fish following your lure speeds up on the forward sweep, and the abrupt stop of the lure puts it right in their face, and then the next sweep is also the hookset.
This might not work with big-lipped lures if you're trolling just above weeds, but with lures like spinnerbaits and rat-l-traps, it's deadly.