Download instructions: Click on a pattern's title to download the image, then print, scaling to the size of your pumpkin.
Carving instructions: Your secret weapon for carving these beautiful patterns is a pumpkin carving saw, included in pumpkin carving kits (available in stores). The saw allows for much more intricate carving than traditional knives.
After opening and cleaning out the pumpkin, size and print out your pattern of choice and tape it where you'd like to carve on the pumpkin. Using the poker tool (also included in the carving kit), poke holes along the outline of the pattern to create dotted lines on the face of the pumpkin. Be careful, some of the more intricate patterns require much more detailed lines.
Once you have created your dot-to-dot pattern, remove the paper and use the carving saw to cut along the lines. A good rule of thumb is to go from left to right (if you're right handed) and cut smaller holes first to maintain stability.
Another fun tool available for use is a dremel-style sculpting tool. This allows you to easily carve only part way through the pumpkin, which creates glowing lines and areas.
Have fun carving your colonial pumpkins.