When doing a multi-block print I cut the keyblock first then transfer the image to all the blocks per color/s. A sheet of acetate serves as the transfer medium, but I'm sure any coated paper such as glassine would work too. Speedball water based inks is my preference for this process since it dries the fastest and prints nicely on acetate. I make sure my registration system is set up for easy and accurate registration so that I don't have to figit with it later. After the ink dries I wash the it off the plate, leaving a stained-in ghost image. Also, the image on acetate, when laid over each print in progress helps me to know where to cut.