I haven't actually pieced one yet, but I have been doing some research. Several sources say to starch the fabric before cutting out the diamonds. Helps to keep the bias edges from stretching too much. Also, you can sew strip sets, so you aren't handling individual diamonds, but a strip. Offset the start so you don't have as much waste when you cut the strip on the diagonal. You will need different strip sets for each section of the diamond, but you use 2 of each except for the center one.
Debra
Ontario, Canada