Fill a large pot halfway full of water and bring to a simmer. Add the crab boil pouches and simmer until the water is heavily seasoned, about 5 minutes.
Add the potatoes and cook until tender, about 15 minutes. Remove with a slotted spoon and set aside. Add the corn and cook until tender, about 5 minutes. Remove with a slotted spoon and set aside.
Thread the potatoes, corn, sausage, and crawfish on 12-inch metal skewers. Season the water with the juice of the lemon and salt, to taste. Submerge the skewers, handle side up, into the simmering water and cook until the crawfish are bright red and cooked through, about 5 minutes.
To serve, place on newspaper and eat with hands.