Bullion fringe will look great on the valance edges. I am not sure how it will lay on the sides of the panel, especially with the lace curtain underlay. If the fringe is to replace the lace curtains, I suggest pinning first and make sure you are happy with the look. To apply, I would hand tack instead of using a sewing machine. If you decide later to make a change, it's easiest to remove. Fabric glue would work also, but that is way too permanent for me. Also, when you cut any kind of fringe, it unravels like crazy. The fabric store will tape (clear tape like Scotch tape) the edge before cutting. Use that same technique and tuck the taped edge under when you are adhering. Good luck.

That fringe doesn't have a decorative edge, so it was meant to, and looks better if sewn between seams. If that doesn't matter to you, then hand sewing would be the only option, especially on velvet.