I also got one of those carving kits from supermarket a few years ago. It had a set of templates that you sellotape onto the pumpkin then use a thin pointy tool to mark round all the edges. Then when you take the template off you can see the lines to cut and it's a bit easier as it's already perforated through the skin. There's a couple of little saws in the kit. They're really narrow so you can do quite intricate patterns.

Getting as much of the insides out as possible makes carving easier too since the walls you're carving are thinner. Very messy and makes your wrist ache but well worth putting in the effort - the kit has a scoopy tool which works quite well

Last year my OH took photos of us doing scary (sort of!) expressions then used a software package to turn them into black and white templates and get them the right size for the pumpkin. They worked really well. We've got some photos somewhere. I'll see if I can find them and post them up

This is the kit I got
http://www.pumpkincarvingkit.co.uk/