A strong fall garden show happens by design, not accident. Many gardeners simply throw some pansies, mums, or kale into their flowerbeds. These plants are nice, but they're overused and very limited in the looks they can provide.
Instead -- or perhaps in addition -- select perennials, trees, and shrubs specifically for their autumn looks. Mix it up: Different types of plants add their own special contributions to fall landscapes. Trees provide great backdrops and color up high; shrubs do the same, but at a middle elevation; grasses provide year-round interest but really shine in autumn with their graceful form and delightful seed heads; and some perennials bloom in fall with an energy equal to anything you'll see in spring.
Containers also can be designed for fall interest. Grasses, perennials, and annuals all are available in garden centers in fall -- you can often find great closeout deals! -- and can be combined in beautiful, frost-tolerant pots.