From the white/black print background fabric - cut:
6 - 4" squares;
5 - 3 1/2" squares
1 - 1 1/2" X 20 1/2" strip
2 - 1 1/2" X 12 1/2" strips
From the Cool fabric - cut:
6 - 4" squares
From the Warm fabric - cut:
2 - 1 1/2" X 20 1/2" strips
1 - 1 1/2" X 12 1/2" strip
As you can see from the picture above, I chose red for my Warm color and Blue for my cool color to use for this tutorial. Also, the strips are folded in half so I could fit them all into the picture. It is so handy to have my boxes of pre-cut strips and squares. All I had to do was find enough squares of the same fabric for my Cool and then two strips from my 1 1/2" box for my Warm. I am going to dig through again tomorrow to make another block. Okay, carry on - sorry I got side tracked.
Now that everything is cut, you are ready to sew. Either draw a diagonal line or fold and press a diagonal line on all 6 of your background 4" squares. Place one background square right sides together with a Cool fabric 4" square. Sew 1/4" on both sides of the diagonal line. Repeat with the other 5 squares. In the picture below, you can see my pressed line and I am sewing 1/4" from that line.
It's a little hard to see, but I have sewn two lines of stitching on either side of that pressed diagonal line. I turned it over to the blue so it might be easier to see the stitched lines from this side. Cut on the diagonal line. Press toward the Cool fabric.
Square up each square to 3 1/2" and set aside.
Sew one Warm 20 1/2" strip to a background strip of the same size. Press toward the Warm fabric. Sew the second Warm strip to the other side of the background strip. Pressing once again toward the Warm fabric. You now have a WBW strip. (sorry - no picture of this)
Cut this WBW strip into 4 - 3 1/2" squares and 4 - 1 1/2" pieces.
Sew one 12 1/2" Background strip to a Warm strip of the same size. Press toward the Warm strip. Sew the second Background strip to the other side of the Warm strip. Pressing once again toward the Warm fabric. You now have a BWB strip. (again, no picture)
Cut this BWB strip into 8 - 1 1/2" pieces.
Create 4 - 9 patches sewing two of the BWB on either side of a WBW piece. Press toward the middle. (finally a picture of the finished 9 patch block and a partial of the WBW strip block)
Sew one 9 patch block to one strip block lining them up as in the picture above. Sew the second 9 patch block to the other end of the strip block. Repeat for one more set. Now sew the remaining strip blocks to a 3 1/2" background block with the warm fabric to the block. (see the picture below)
Press the top and bottom strip toward the outside and press the middle strip to the middle and you will be able to butt up those seams when you sew the entire group together like the picture below.
You now have your center of the block finished and are ready to add the outside borders.
To create those borders, you need to sew a 1/2 square triangle to either side of a 3 1/2" background square. Make sure your triangles are turned opposite of each other as in the picture above. Go ahead and sew all 4 of the remaining 3 1/2" squares exactly like this. Attach two to either side of your center block.
Add one 1/2 square triangle block to either end of your leftover strips making sure the triangles face the same way as the one next to it. (I don't have a picture here for you to see, but you can refer to the original drawing at the beginning of this tutorial or the picture below of the finished block. Attach the borders to the top and bottom of your block matching seams.
Be sure you pay attention to your block and the direction of those triangles or you will end up with a block like the one below. I had to "un-sew" and then put it back together to get that beautiful block above. Just wanted to show you that I do make mistakes. However, I don't always take pictures of them and then post them on here. I thought you might get a kick out of this one, though.
Enjoy making this block and I can't wait to see what all color combinations you come up with. I hope this tutorial is helpful and doesn't totally confuse you. If you need help or clarification feel free to send me an e-mail.