Here's what I did in a very clayey, poorly drained back yard recently....I made swales and berms or raised beds right next to each other, the yard was relatively flat so I oriented them north-south for light distribution. I started by digging out the swales and turning the sods upside down over the adjacent strip of undug ground, thus doubling the thickness of the topsoil layer...these became a set of raised beds. I then filled the trenches with every imaginable free organic matter source...branches and sticks, leaves, paper and cardboard, wood chips, etc. Any weeds that were pulled or garden debris that was generated was simply thrown in all summer and fall. Thereafter, every year I would shift the soil from one or more of the beds on top of the stuff in the adjacent swale, thus creating a sort of hugel-bed. At the same time I would bury any half-finished compost, humanure compost, and anything else both useful and also needing sequestration for a few years. The end result after several years is that the entire area consists of a set of raised beds with coarse organic matter under them, with the beds above background grade, but with ready access to moisture accumulating in the swales. Given the quick breakdown of organic matter in this climate this process could probably continue indefinitely. In a climate like California, a policy like this also gets along very well with fire suppression, since one is continuously burying organic matter under the soil, rather than leaving it on top where it can burn.