We have a dirt backyard right now that is full of big clod things and sticks (I've gotten most of the stones out I think). Anyways, it was just roto-tilled with a machine the other day. I've been reading up about lawn seeding, types of grass, etc...but what I can't figure out is what I do to prepare the dirt. It's about 2000 sq feet and like I said, covered with these big hard clumps of dirt. Do I rake them all out and get rid of them? Or do I some how break them all up, or just smash them into the ground? Is there a machine I can rent? We don't have a lot of money to spend on this project...but I do have time. Any advice would be much appreciated. I can take a picture too, if you need to see it.