To make the Larger center Half Square units, place a Color
3 4-7/8" square right sides together with a Color
1 4-7/8" square with all edges aligned. Lightly draw in
the diagonal on the back of the top square. Sew 1/4"
from the drawn line, on each side of it. Cut apart ON the drawn
line between the rows of stitching. This will give you two Half
Square units. Press seam to darker side. These should measure
4-1/2". Repeat with the two remaining
4-7/8" squares to make two more.
Then do the same thing using Color 2 and Color 3
2-7/8" squares to make eight Half Squares in that size. Those
should measure 2-1/2"...