You turn the shock, not the screw driver. I know that sounds obvious but there's a whole thread somewhere trying to explain that to people who just didn't get it. You use the screw driver as a lever, not as a driver. There's also a tool in the tool kit under the seat if you still have it.
The number facing out should be the same on both sides. 1 is the lightest pre-load and 5 is the heaviest. I ran the shocks on my Standard on 3 and felt they were better than on 1, which was how they came out of the factory. With the Roadster shocks I have now I find 2 to be good. You'd only use 5 if you're riding 2 up and/or carrying a lot of luggage - or a really big boy. I weigh around 80kg by the way. Try a few different settings and pick the one that feels best for you.
Incidentally, from your avatar (and seeing as yours is an '05) you have a Standard, not a Classic. Pretty sure that both had the same shocks though.