I used the Marti Michell feathered star template set P. I've had the templates for many years but I never used it for the feathered star, I used parts of it for other things.
There may be a better way to do the feathers. I cut out every single triangle and sewed them together individually. It would be much easier and more efficient to sew them in squares on both sides of a center line and then cut them in two.
It wasn't too hard to make, I just had to be very careful about the 1/4" seams. I did a scant 1/4" at first but even that little bit made the row of feathers that attach to the sides of the star points a smidgen too long. I had to re-sew the seams a TINY bit to make them fit.
The way it is put together is in rows so there are no set in seams, which is a pain to do. It also uses partial seams, which go together quite nicely when you get used to it.