If you use the plano style boxes as I do. The best way that I have found is to make sure all the heads on all the flies in the box face the same direction. Not much I know but what this does is allow you to keep the longer hackles and bucktail on these flys from becoming warped in all different directions. You put them all in the same way and when you place the box in your vest or whatever you use point the heads down. This way your streamers will maintain their proper shape. This is just something I have learned over the years and has made a huge difference in keeping my flies in good shape.