This video demonstrates how to square up a quilt block. Once you have your quilt blocks made up you have to square them so that they are all even sided and the same size. Take your most uneven sided square and lay it down. Place a square ruler over it. Line the ruler with the sides. Once you've measured the square determine how much should be cut from each side. Use a rotary cutter to cut each side down so it is even. Then lay the square ruler over the square again to measure your success. Re cut if needed. Then repeat the process with all your squares so your project will be even.