HST baby quilt

I found this really neat way of sewing half square triangles at That Girl That Quilt blog. (Link below) brilliant, right? Why have I never seen this before??? I thought it was the perfect pattern for a baby quilt for my hubby's friend and his wife's new baby girl. http://www.thatgirlthatquilt.com/2011/03/have-stitchin-weekend.html?m=1

So here we go: 

You put two squares together right sides together and see a quarter inch seam the whole way around (even corners) and then cut along the diagonal. I used 10" squares, which made 6.5 inch squares. I needed three additional blocks so I cut 7" squares and then cut them on the diagonal and sewed two together on the diagonal. This have me my 21 purple/white blocks, 21 purple/green, and 21 green/white. 

You can kind of see my chicken scratch layout and calculations. I'm a visual person. I have to see it before I can do it. I'm sure it makes zero sense to you but it's perfectly clear to me ;). 

It is very important to square up your blocks! I used a 12.5" quilters square ruler. Even though I used my 1/4" foot, some of my blocks were almost 1/2" big and some were just barely the right size. Agh! 

Next up: layout! .....