Most sod sites recommend renting a lawn roller to prep/level the soil prior to installing and after putting down the sod to eliminate air pockets so all the roots are in contact with the soil. I found a 50 gallon plastic drum filled with water was much better because of the additional width. I wouldnt do this on a serious slope, though. This was actually the funnest part of the job.
Lasagna is spaghetti flvored cake. Just like this tiny ad: