Log Cabin blocks are easier to do on an odd grid than on an even grid. It works with a 6 inch square though, if you start with a larger center square. This one is a log cabin variation called Bullseye.
All you will need is 1.5 inch strips of indigo and background along with a 2 inch square of indigo. The indigos can be the same or different.
Here are the pieces you will need:
1 - 2 inch square of indigo
2 - 1.5 by 2 inch strips of background
2 - 1.5 by 4 inch strips of background (notice that it looks shorter in the picture, I figured it out as I sewed the first round)
2 - 1.75 by 4 inch strips of indigo
2 - 1.75 by 6.5 inch strips of indigo
Add your star points and your first sampler block of the month is ready to go.