The old "unfinisher" me would have stuffed these pieces into a box. I am determined not to continue down that path. This pattern went together very quickly. It is a little tricky on which way to cut the half squares. Just remember the secondary colors go the opposite of the primary colors.
When you are adding the sashing strips to the half squares, press them in half to find the middle. Align the middles then pin together. When you square these up, it is the small triangle that get trimmed down.
Sew the 4 quarters together. Since everything is squared up, they should line up well.
Add the last 3 sashing strips.