I saw this on Simply Quilts once and now use it all the time. It's best if you use squares that are divisible by 3.
6, 9,12 inches. I did a swap on the internet for these and used the 6 inch square to start. Once you have mastered this it's fun and easy.
Magic nine patch: Take 2 squares - say 6" for simplicity sake - lay them face to face and sew a 1/4" seam on 2 opposite sides. Measure in 2" from the each sewn edges and cut,- from the raw edge near that seam you just sewed. press open. You now have 2 blocks of 2 strips and 2 extra strips of fabric, sew one of the leftover center strips to each block. Now you have two 3 strip blocks in alternating colors. Lay one block face up with the strips running up and down. Lay the other block on top face down with the strips running the same direction, flipped so seams butt. Sew 1/4" seam on the 2 opposite sides where you cross all 3 seams and measure in 2" from sewn edges and cut. Sew the extra strips one to each block and viola! you have two 9 patch blocks. Make sense? Your finished block will be 1 1/2" smaller than the size you started with, so this block should be 4 1/2".
I love this technique, it's so quick and easy!
Hope you can understand these directions, I had one with pictures but can't find it on the net.
denise
PM me with questions.