Carve out the pumpkin, using a short, strong and sharp knife - a Stanley knife is ideal. Don't push too hard on the pumpkin with your other hand while you are carving or you could collapse it.
Check it with the candle
When you've finished your design, light a candle and put the lid back on the pumpkin. If the light goes out, you need to make some wider cuts in pumpkin to allow for better air flow.