I'm installing a new lawn. One side of the lawn has pretty good loam and was full of weeds. The other side had awful loam, so much so that not even weeds were growing. I rototilled and raked all of it. Nice and smooth. I then bought some Scott's Premium Top Soil, which has Peat Moss mixed in and put a couple of inches on top of everything. My problem is that the new top soil is so fluffy that everything is very lumpy and doesn't look smooth. I had planned to rake it smooth, but it has such a different texture than the loam underneath it that when you rake it, you end up just pulling it off the underlying loam and nothing gets smoothed out. How do I get this to be smooth? I thought about rototilling it all again with the top soil on top, but then it's going to mix heavily with the underlying loam (including the bad stuff) and I'm afraid the grass won't grow well. Suggestions?