When making scrap quilt units, I make my HST using pre-cut patches placed right sides together. Then I take a long emery board to use a straight edge diagonally corner to corner. Fabric is stabilized while drawing line. Sew .25 inch each side of line, cut on drawn line, trim to size. I do six or more at a time using chain stitching technique. Down one side of each, turn, down the other side, slash on drawn line. Ready to press and trim as needed. Almost instant gratification as pile of blocks pile up!