After reviewing the website that you referred, I have combined their method and my own by trial and mostly error. Mark the 1/4" seam allowance on all 4 sides, at the points the left and right seam allowance will intersect and cross each other.
I push my pin in the intersecting mark on both pieces that are being sewn and guess what? The piece comes out PERFECT!!! I have almost got the middle part of the quilt finished since I don't have to take out and resew to get the seam perfect. Thank-you again for helping me.