I have a client that wanted me to mix sand with his totally clay yard; just in the front, leaving the back and sides all clay. I do not have a lot of experience with clay, not knowing if this was even a good idea because I like black dirt. Anyway the problem was it has been raining so the clay is real wet. i went there today and spread a thin layer of sand on his front clay yard. i then mixed it all with a rototiller. this left clumps of clay everywhere. My question is this. Should i have mixed these soils in the first place and how can i get the clumps to break up better when it dries up?