Use a serrated utility knife with a pointed tip to cut through the top of the pumpkin. With the blade at a slight angle, cut out a star shape to serve as the lid of your jack-o-lantern. Scoop out all the seeds and pulp with a large spoon and place in a bowl of cold water. The pulp will sink, leaving the seeds floating at the top. Set aside for roasting.
Use a rolled up kitchen towel to keep the pumpkin steady at the base. Draw your design onto the skin with a non-permanent marker. Use a vegetable knife to cut along your lines with long, smooth strokes. Take care not to use too much pressure. Place your forefinger along the back of the blade for better control.
When most of your design is cut out, return with a paring knife to clean up the edges and add any final details. When finished, light a candle inside and place in a spooky spot.