Step 1: Cut out top of pumpkin and scrape the inside clean.
Step 2: Using a real vine or a vine pattern, transfer design to pumpkin. (To create your own pattern, use varying sizes of your favorite leaf shape, and then draw a vine between the leaves.)
Step 3: Carve leaf shapes by cutting completely through the pumpkin or by scraping a shallow relief. You can combine the two methods, as shown here on the smallest pumpkin.
Step 4: With a scraping tool, carve vine stem about 1/4 inch deep, being careful not to break through the pumpkin flesh.