I used one skein of Charisma Big! in Steel and one skein of Bernat Softee Chunky Big Ball in Black. Around 650 yards should be fine for this pattern. One square should measure about 8” across before blocking and around 9” after. It makes a 30”x30” blanket, after blocking. Any bulky weight yarn will do, though. If you want a bigger blanket, just keep making more squares!