Add the potatoes, corn, celery, bay leaves, lemon juice, lemon halves, garlic, onion, green bell pepper, Louisiana boil powder, Cajun seasoning, 2 teaspoons of the salt, pepper, and about 8 cups of water to a large pot, or a dutch oven that has a lid. 

Place the pot, on the stove, over high heat. Bring it to a boil and then reduce the heat to a simmer, cover pot with the lid. Let it simmer for 20 minutes, or until the corn and potatoes become tender. 

Taste the broth and add more salt and/or seasoning, if needed. 

Then add the crawfish and sausage and stir to combine. Bring it back up to a simmer and cook for another 5 minutes with the lid on. Turn the heat off, with the lid, and let everything soak for 10 minutes. (The longer you let the crawfish soak in the broth, the spicier they will get.)

Drain broth and serve immediately with lemon wedges.