Step 10: Sew it Up
It's pretty common to use metal bailing wire to close the pig. If possible, just get regular non-galvenized standard metal bailing wire. Other metal wires will work as well but will likely cost more.
Start at one end and simply sew the pig shut all the way to the other. You can use a variety of stitches to close the pig, but what's easiest to me is just to grab the two laters of skin, hold them together like a fabric seam, and stitch them together using big looping stitches.
A few words about giant sewing needles for meat...
One time I roasted the pig I was without my trusty oversized trussing needle that I made. It was pretty annoying to push the bailing wire through the pig's fatted belly skin with just a pair of pliers, or worse, by hand as you can see in the second photo above. The giant needle is the way to go for sure if you have time to make one and really helps in the stitching step.
To make the giant needle:
Get some 1/4" or 1/8" steel rod and grind the tip to a point on the grinding wheel. Then, pound the other side of the rod flat using a small sledge and an anvil. Drill a small hole through the pounded side and you've got yourself a freakishly large needle! The bigger the better on the needle as pushing it through the belly skin is a one, or maybe two handed job. The more steel there is to grab when your hands are all slick and you're staring at a 60 pink pound pig in front of you, the better.
Once the pig is all sewn up, the final step, which is totally optional, and probably not healthy for the future of our world, is to have a small child tenderize the meat with a baseball bat.