This is what my book says, but I havent' tried it yet. I will try later and show if it looks okay.......

"Basic Grosgrain ribbon.
begin wiht a basic rectangle filled with a linear gradient with an angle of about 45 degrees. Draw thin, vertical lines along the width of the rectangle. duplicate the original layer twice, and then use the deform/transform tool to shrink the height of each of the duplicate rectangles to get one thin rectangle along the top edge and one along the bottom edge. Merge the layers and add some shading. "

I hope that makes sense. I want to give it a try. Someone else may have better directions, I took that from my book.
Show us what you come up with when you give it a try.

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