I put a pin on the center of each block and the hoop it, attempting as much as possible to keep thet pin in the center of the hoop. Select the stitch to be used and adjust the position of the needle to start at the site where the pin is. Remove the pin (very important) and start stitching. The design will be centered. If the design is almost the same size of the hoop you will need to hoop in the the center because you will have very little space the move it around. Your machine came with a grid that helps you center designs.
Maria