Here's what you'll need to make your own:
enough fabric for (6) 3.5" squares, (6) 2.5" squares and a button cover
fabric glue, scissors, needle, thread, etc.
cardboard for a template (optional)
button covering kit
 Start by cutting your fabric to size
You could use multiple fabric scraps for a colorful flower...
but I chose this fabric since it had a bunch of color/pattern in it already.
 Starting with a single square, fold in half diagonally
 Fold bottom left and right corners up to meet the top in the middle
 Flip your little square over and fold the bottom and top corners toward the middle...
(you'll be folding in toward the seam on the other side - see picture below)
 Fold petal in half (along the dashed line illustrated above) so the small triangles you made in step 4 are touching.
Voila! Your first petal... tac together on the bottom so it doesn't come apart.
Cut off extra fabric at the bottom of the petal when you're finished.
Repeat these steps to create the other 11 petals.
When all of your petals are made, you're ready to construct your flower:
 Using a needle and thread (or in my case, embroidery floss) thread your petals together.
Once you get back to the first petal, try a small knot to secure.
Make sure you don't pull to tight or your flower will get distorted.
 Finish by adorning with a button of your choice!