Step 1: Fill a large pot half to two-thirds full of cold tap water. Add 1 tablespoon salt and bring the water to boiling. Step 2: Add crab legs to the boiling water, bending and tucking the legs so as much of the legs are covered as possible in water. Return the water to boiling. Step 3: Cook the legs, uncovered, for 4 to 5 minutes or until heated through, adjusting occasionally with long tongs to make sure they heat evenly. Step 4: Using long tongs, remove the legs from the water. If desired, rinse legs; drain well. Serving Crab Legs. When serving, keep things simple and let the crab legs star.