With the advent of the automatic dryer, their popularity diminished. Today, clotheslines are making a comeback -- and for good reason: There is something very satisfying about drying laundry on a line. Air-dried linens have a crispness that you can't get from a modern dryer -- not to mention the fresh, sweet smell your clothes gain when hung out to dry.
Martha prefers the strong, natural fiber of cotton line, but if you live in a very humid climate, you may want to use plastic. The height of your line will depend on your own height, but seven to eight feet is a good rule -- if the line sags, your linens will still be safely off the ground. The following technique calls for fifty feet of line; this measurement will vary depending on the distance between the trees from which your line will hang.
Resources: Heavy-duty hooks, pulleys, line support, line tightener, and clothesline rope are available at hardware stores.