http://www.fishforum.com/viewtopic.php?t=3738
This is the sticky which explains it, I hope it does anyway but I will explain a little here about the shrimp/prawn cycling method.
All you need to do is set up the tank, stabilize the temperature, set up the filter and throw in a raw peeled full prawn. The prawn breaks down slowly and creates ammonia which feeds the ammonia eating bacteria. This in tern creates the nitrites which are eaten by their own bacteria. This makes nitrates which are removed by doing water changes.
The whole process when done from scratch without any seeding can take from 6 weeks to 3 months. If you take some gravel from the old tank, wrap it in some nylons and place it on the bottom the bacteria can and should produce faster. This can speed up the whole process to about 3-5 weeks if you are lucky. If you let the whole prawn disintegrate before adding fish it is said that you can add pretty much any bioload you want to because of the massive amounts of bacteria that will grow from such a mega source of ammonia and nitrites.
Hope that helps. I will edit the sticky to say prawn instead of shrimp, is a little confusing now that I have read it for the umpteenth time.

And yes I do read it even though I wrote it. Is why I wrote it all down because I would never remember it all myself.