Cut squares, draw line diagonally on back, stitch 1/4" on each side of line, cut on line = (2) 1/2 square triangles. Trim to 13 1/2" . I would use graph paper to figure out how many you need for king size quilt. ( often 100" square) {49 -- 7 across by 7 down} 13" finished (13 1/2" unfinished) would give you 91", which you could then add 5" border to to finish & bring to the 100"