trolling speed: just like trolling anything, put the lure in the water just beside the boat, start moving. if you like the action you're getting on the lure, that's the speed to use :-). if you have a sensitive tip, you can see the "bobbing" of your spoon when trolling. as a short answer, you really don't have to go very fast at all. i also would suggest doing this at early morning or evening when the water is calm.
line depth: this is a bit tricky i find. if your lure/rig isn't very heavy, then it has a tendency to "plane out". for instance if you try dropping your lure right beside the boat on a lake with even SOME waves, you will find that you will be moving away from the location that your lure is dropping. the same idea goes when you're trolling -- the lure may have a tendency to be plane out rather than stay deep. solution is to keep a somewhat heavy rig if you want to troll at a significant depth. otherwise, expect to lose some depth as you move along. sorry if my explanation isn't clear.
for jigging: try just jigging beside the boat. understand what the jig is doing when it's dropping -- that's typically the movement that triggers a hit as the previous poster indicated. don't jig furiously though. i would imagine something like how you might fish a hula-popper or other surface lure: jig jig, wait a bit, jig, wait a bit, etc. just play around a bit.