I'm going to try and catch up on triangles a little, so expect to see more of them over here.
Print or trace the block diagram onto foundation paper, number, and cut out as in the photo.
You have to mirror this diagram.
Software users: remember to change the block size to 5"x8".
If you're not using freezer paper to foundation piece, print or trace the bottom section of the block onto the dull side of freezer paper and cut out.
Foundation piece all the numbered sections and trim the seam allowances to 1/4".
Cut a 3"x10" section out of main block fabric. Cut a 3"x10" section out of background fabric. You can cut these smaller, but I like being on the safe side.
Cut the little triangle shapes out of the freezer paper bottom section.
Iron the freezer paper to the right side of the main block fabric rectangle. Leave enough fabric around the edges to be able to trim the seam allowance to 1/4" later.
Cut out the triangle shapes, leaving a small seam allowance to turn under.
Lay the background fabric rectangle right side up on the table. Lay the main block fabric rectangle (with the freezer paper) right side up on top of it.
Baste layers together firmly.
Turning under the seam allowances, applique around the triangle edges on both sides of the block section. Trim the seam allowances to 1/4".
Remove the freezer paper and cut the excess background fabric away on the back of the block.
Sew the three small block sections together.
Referring to the block diagram, complete the block by sewing all sections together, starting with the bottom section.