The only tools used are in the picture below.
Serrated pumpkin carving knives (from those kits you can by ANYwhere around Halloween)
X-acto knife with various blades
Large spoon or pumpkin kit scoop to empty out the pumpkin innards
Ball point pen or fine-tipped Sharpie (Sharpies can get annoying as the wet pumpkin can make drawing a pain)
Remember, this is EXTREMELY challenging, but I always like to post an instructable to show people each year how I did it. Enjoy!