In no particular order:
Have the soil analyzed to determine the levels of elements and pH.
Rotary till it.
Rake it to remove all non-organic materials.
Add compost or if you have time, plant winter wheat or ryegrass and let it grow through the off-season then till it in.
Do a really simple analysis of the make-up: using a small garden spade, remove a sample of the soil, collecting it from the top to about six inches deep. Remove all foreign matter from it then put it in quart (liter) jar. Add enough water to fill the jar about 2/3 of the way. Shake it vigorously for as long as you can, then do it again and again, until every tiny piece of soil is completely dissolved (it helps if you break it before putting it in the jar.
Set it aside for at least three days, then see what the levels look like. You should have a small layer of clay, a small layer of sand and a decent layer of silt. (I forget the ideal ratio, maybe 25-25-50?).
I have an area where nothing, not even weeds will grow and it has about one percent each of clay and sand, with the rest silt. It will not hold water and thus nutrients. But this spring I added a lot of compost and some potting mix to it and it turned out to be great soil.
YMMV,
Mike