You may "get away" with running without a tune but you'll never see the full potential of your combo until you do.
To set timing (assuming you have EFI) pull the spout plug (little plug hanging off the distributor). Loosen the distributor bolt so that the dist. will turn but it's still snug. Hook up your timing light and make sure your wires and nothing is close to the serpentine belt and everything is safe, then start the car. It'll run funny because the spout is unplugged. Shine the light on the balancer and read what the pointer is showing...then turn the dist. left or right to adjust the base timing. Most cars like 14 degrees base, but every car is different. If you run 93 octane, i'd set it at 12-14 and leave it alone until you get it tuned. Snug down the hold down bolt and read the timing again just to make sure it's where you wanted it and you're set. Don't forget to plug the spout plug back in before you drive it.