Before opening or cooking clams, wash and scrub the shells in cold running water with a small brush to remove all traces of sand and grit. For soft-shell varieties, whose open shells collect sand, such as razors, steamers, or geoducks, prepare a solution of 1 cup salt to 3 quarts cold water in a bowl; stir until the salt dissolves. Make sure to prepare enough solution so that all the clams will be submerged. Add the clams, set the bowl in the refrigerator, and soak overnight.
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