Originally Posted by roxiej
Looks like your crease before the ribbon center is not tight enough.
I agree. When you're stiching your bow pull as tight as you can and then wrap it a couple of times (pulling as tight as you can) with the thread, before you tie it off. Use a strong thread (like upholstery thread), or the thread can break.
Also, like some of the others suggested, try using 1/4" ribbon on the center.