This step is a little tough to do for the first or even second time. I've taken a pig butchering class from 4505 Meats
in San Francisco, CA and I still have trouble breaking whole animals down quickly and easily. The important thing to remember is that the meat will be tasty no matter how it comes off the bone, so have a drink, don't stress, work fast and dig in.
First, sharpen a knife, or two, and find an extra person or two to lend you a hand. Work the knife between the shoulder and hip joints to remove the four legs from the roast. These roasts can be treated as their own discreet pieces and handed off to another carver. By far the most meat will come off of these pieces which include the pork shoulders and boston butts.
You should be left with the trunk/torso of animal. This contains the belly, loins off of the back, tasty marbled meat from the neck and jowl, and the also delicious, but hard to work for rib meat. Save the skin and begin to carve out the loins as that's the most easily accessible and edible meat that will come off this section. After that, go after everything that's left sorting the parts into different serving platters and pots. Skin is good to snack on - people will eat it so don't throw it away! Bare bones make a great soup stock. Dogs like cartilage and strange off-cuts not suitable for serving. The best meat should go onto platters for your guests.
It can be useful to cut the ribs with a hack saw off of the spine. If you are pulling the meat and don't want to serve "on the bone" pork, just work the meat off the bone by hand. I leave the spine relatively intact once the loins are off - there's definitely some meat along their but it's best to pick at it with some friends rather than try to spend the time removing it so you can be served.
Place a knife between two of the neck vertebrae just behind the ears and cut the head of the pig off. For some reason, everyone really likes playing with the pig head.
Once you've gotten the legs and carcass carved up pretty well, serve your first round since you can always continue carving as people begin to eat so that the meat doesn't get cold. In general, it's taken me between 30 minutes and 1 hours to carve up all the pork and chicken and people's mouths can only water for so long, so best to serve and then keep working as people begin to eat.