If possible have the top seam facing into the machine and the bottom seam facing away from macine. this lets the top seam butt into the bottom seam. sometimes if can't do the whole seam this way I will stop and turn the block over and start from other end. I use clovers fine pins and can sew over them going slowly if have a problem seam. I pin on both sides of the seam into each seam allowance this holds it in place. good luck