For some reason I really wanted to try to make this. I found a wonderful picture of a red bow so that I could examine it. Then I used the pen tool to draw the sections of the bow and made up my own gradient but it was looking the way I needed it to look. Upon examination the gradients in the blow actually follow the lines of the section rather than go straight. Getting Illustrator to do this was hard for me to understand. But I found that if I created a rectangle and applied an envelope distortion ( making sure that distort gradient was checked in the envelope distortion options) then I could use the subselect tool to manipulate the points to the shape I needed for the sections of the bow. Actually this is a work in progress but here it is so far.

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