I find the easiest way to shuck large amounts of lobster is to do it assembly-line style. Crack all the shells first, then pick all the meat.
Step 1: Kill It
It's not necessary, but if you'd like to kill the lobster before cooking it, do so by driving a knife into the center of its head and pushing down to split it open.
Step 2: Grab the Tail
Grab the tail and the carapace firmly in your hands.
Step 4: Set Aside
Set the separated tail aside.
Step 5: Twist Off the Claws
Twist off the claws below the first knuckle. The goal is to keep as much edible meat as possible.
Step 6: Repeat
Repeat with the second claw.
Step 8: Steam
Start cooking by steaming the lobsters over boiling water. The goal is to steam just long enough to get the meat to set. This takes just about 2 minutes.
Step 9: Done Steaming
Sometimes the lobsters tails will still be twitching a tiny bit even after the initial two minute steam. This is a reflex reaction. Don't worry about it.
Step 10: Roast
Transfer the lobsters to a 350°F oven and roast until each piece hits 135°F. That's about 7 minutes for the claws and 15 for the tails.
Step 12: Start Cracking
To peel the tails, start by running the under cold water to cool them a bit.
Step 13: Press Hard
Crack the tails lengthwise by squeezing them hard. This will make it easier to split them open.
Step 14: Pull Open
Pull the tails open lengthwise.
Step 16: Wash out the Gunk
Lobsters sometimes have gunk running down their tails (gunk being the technical term). You can wash this out by running cold water into the tract, or if you're chopping the meat anyway, just wash it out after splitting the tails in half.
Step 17: Break off the Pincher
Break off the small pincer. If you do it carefully, you can break it off and remove the shell without taking the meat with it. This is the goal. But it's ok if you don't meet it.
Step 18: Remove the Cartilage
Oops, I broke of the small bit of meat. That's fine. Once you've removed it, pull out the cartilage that extends into the main compartment of the claw and discard it
Step 20: Attack the Claw
Place the large part of the claw on a clean(ish) dish towel.
Step 21: Smack It
Fold the towel over and rap the claw hard with the back of a knife to crack it. If you have an exceptionally soft lobster, you can cut through the shell with just a pair of kitchen shears.
Step 22: Cracked!
If you did it right, you'll have cracked through the shell while leaving the meat intact.
Step 24: Go For The Knuckles
The knuckles have plenty of good meat in them too, see? It's the sweetest, most tender part of the lobster, and my favorite bite.
Step 25: Twist Them Apart
Twist off the knuckles using a dish towel or sturdy rubber gloves.
Step 26: Separate the Knuckles
Each claw will have two knuckles attached to it. Separate them from each other.
Your lobster, perfectly cooked and ready to eat!