I started with a standard headband that I bought at the supermarket. I was lucky that my chosen headband was already fabric covered, but if you are not as lucky, I imagine you could either make a fabric tube to cover it in, or could used a hot glue gun to attach the embellishment.
Next up is to cut and form the petals. Cut eight of each size, I used two different sizes, the shape of which you can see above. You should have a total of 16 pieces of fabric, 8 in one size, 8 in another. The base of each petal is around 9cm (3") once sewn together. Pair the pieces together with right sides facing and sew around leaving the base open for turning. Pink or trim close to the seam as you want to end up with nice smooth curves. Turn right side out and press.
Now it is time to pleat the petals. These are created as box pleats. Box pleats are formed when two equal folds of fabric are folded away from each other in opposite directions along the length of fabric. I tacked them down with a long stitch on the machine, the long stitch is in case I want to alter them later, it make the stitches easy to remove.
Each of the pairs of petals is then sewn together in the centre. The bottom pair I sewed the other way around so all the raw seams are hidden within the flower. Not sure I am explained this well, but the picture above should show how the pairs of petals go together. Press the pairs of petals open to reduce the bulk and stack pairs of petals of top of one another, offsetting them to give the flower effect. Hmm...again not any pictures of the process for this, but the result is above. Basically you should have two pairs of each size of petal. Each of these is laid in the opposite direction from the one previous.
Hand sew through all layers in the centre. This is kind of tricky as there are a few layers so make sure your needle isn't too short. I then attached pearl buttons that I had in the centre to disguise the seam, but you could use one larger button or a broach.
I then hand-stitched the piece to my headband, but of course you could use a hot glue gun.
Go forth and enjoy your special event! Let me know if you make one, I would love to see.