1. Wear Gloves

2. Rip Off the Shell

3. Removing the Jaw and Gills

4. Tearing off the Apron

5. Wash Out the Guts

6. Voila!

Recipe Suggestions

While some people might prefer to clean the crab after cooking, I find cleaning it beforehand easier and better tasting when you actually sit down to eat. Cleaning it ahead of time allows you to remove the shell, guts, and gills from the crab and prevent any of their flavoring from getting into the meat. And removing everything out but the soft shells and meat lets the seasoning and ingredients added to the crab pot to sink in and cook together with the crab meat directly.
Cleaning crabs beforehand will mean fighting off the crabs while they're alive. Until the shell is removed and the crab is allowed to sit for a minute or two, it will be very lively and trying to pinch your fingers as they attempt to clean it. Wear thick gloves for at least the first two steps to prevent any injuries.
To do this, you'll want to hold the crab in the palm of your hand with the crab facing you (it will try to fight back). Place the thumb of your hand that is holding the crab over the part of the claw that connects to the rest of the body for leverage and to keep its claw from reaching back at you. Then, with your other hand, place your thumb underneath the pointed edge of the crabs she'll above your other thumb. Rest your hand on top of the rest of the shell and simultaneously pull the shell up and push the crab down with both of your thumbs (being careful not to separate the claw from the body).
Another way to rip off the shell is to lay it on a flat surface and grip its back four legs with one hand, and ripping off the shell with the other hand in the same way described above.
The shell should come off in one piece. If it doesn't, make sure to check that not bits of shell fell into the crab. It might be a good idea to remove the shells from all of your crabs at once to allow them to calm down after losing their head. This also gets all of the crab fighting out of the way first. This step gets easier with each successive crab and cleaning.
Hold the crab in your palm the same way you did in step 2. Use a butter knife and your thumb to grab the left or right jaw between them and twist and pull it off. Repeat for the other jaw. In a similar way, pinch the gills between your thumb and knife to rip them off. After enough times cleaning crabs, you will be able to attempt scraping down from the back row of gills to the jaw. This will scrape off all the gills and you can rip off the jaw all at once.
No, its not a saying of any kind. It's an actual part of the crab. Still holding the crab, flip it over to find the apron (the spine looking part in the middle of its back). Use your knife to lift up the pointed end of the apron. Once it's up, pull it back towards the rest of the apron, separating it from the body, and ripping it off.
Ah yes, the guts. The part that might prevent many of you from eating crabs to begin with if you were to open an already cooked, uncleaned crab to find them. Really easy step. Take a garden hose with a spray nozzle, set it to jet (or the appropriate setting), and spray the hell out of that crab till the guts are gone.
The crabs are now cleaned and you can place them into your crab pot, face up, and season to your liking. Enjoy your crabs, cleaned the CORRECT way, and all their delicious goodness.
One recipe for cooking is with Old Bay sprinkled on top of each layer of crab that sits on top of a mixture of water and beer (Chors Light because it's cheap and you're just getting the flavor and liquid to steam) that the first layer or two of crabs sit in. Place two sticks of butter on the top layer
Another way to cook crabs, and my favorite way, is with sliced pepper and onions, diced garlic, and chopped parsley sprinkled on layers of crabs (garlic and parsley used sparingly to desire) on top of a mixture of water and white wine (again, cheap cooking wine). Place two sticks of butter on the top layer. You can also use Old Bay to season the crabs, but used less than the other cooking method as to not overpower the crabs since it already has many flavored going.