The author improved her clay soil dramatically over a 3 year period. My notes:

  * Add a layer of organic matter. 3-6 inches and work it in. Manure can work its way in on its own
  * heavily mulch in the fall
  * form soil into raised beds to help with drainage
  * Aeration. Broad fork or digging fork.
  * Clay busting plants: plant Daikon or plants with very strong tap roots, but fibrous roots can help as well
  * Don't leave soil exposed.