剥虾壳。 去虾线。 下锅前，要把虾浸在冷水或冰水中。

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The shrimp should be in cold or ice water when you peel it. To peel the shrimp, just pull off the head, if it's still attached, along with the legs. Start with the head end and pull off the outer shell. You can decide whether you want to leave the tail tip on for presentation, or take it off for eating convenience.  Place the shells in a plastic bag and seal it shut to throw them out.     If you want to use the shells to make shellfish stock later, just seal them in a plastic bag and place it in your freezer.     You can leave the shell on to keep some of the flavor, though this will make the shrimp a bit harder to eat. If you want to do this, you should cut the outer edge of the shrimp's back with kitchen scissors, so you can devein the shrimp easily.    You should always remove the veins from the shrimp before you cook them. To do this, take a small paring knife and cut along the outer edge of the shrimp's back. Cut at least 1⁄4 inch (0.6 cm) into the back, enough to reach the vein, which will be a dark greenish color that contrasts with the paleness of the shrimp. If you can see the vein, just pull it out with your fingers or with the tip of your knife. If you can't see the vein, then move on to the next shrimp. Don't leave them out in the kitchen as you prepare the rest of the recipe.