The arrangement really depends on how many pieces you decide to hang on your staircase. If they are all the same size and only have a few, you might want to hang them diagonally making their way up the stairs. In turn if you have a variety of sizes and quite a few pieces, you might want to do 2 or 3 groupings along your staircase. Also, try to position the items in a manner where they will not be knocked off by someone's shoulder as they make their way upstairs.
