Hi Lucio, you need to go to this url:
http://www.quiltingboard.com/picture...22-t21995.html
Eddie explains how he does it.
Basically, he took a layer cake (10 inch squares) and cut each square into 4 equal strips (2 1/2" each) then cut each 2 1/2" by 10" strip in half but instead of a straight cut, it was a diagonal cut.
I have figured it out that one side of the cut strip is 6 1/4" and the other side is 4 3/4". Read through the posts that Eddie wrote. I'm thinking that some tape on a square up ruler marking the position plus using the 45 degree angle will be sufficient for cutting the strips. Practice on some scraps first.