Here's a small diagram I did in EQ for you. You do not want to make separate stars and then sew them together. The key to the design is that each star shares its white spaces with the stars around it. Can you see the tumbling blocks in the design? I would approach this as tumbling blocks and mark it off in groups of three. Create each tumbling block in the right colors and then sew them together to form the stars. I'd start with a blank grid and color them with colored pencils and take my cues from there.
Sound reasonable?