When I make a portrait, I typically add the background last & do something unrelated to the original picture. Unfortunately, with my latest piece, I have used so much of my energy on the face, now that it is done, I have hit a creative block. I do not know what to do for the shirt and background.
Here is what it looks like now with a few fabrics auditioned against it:

I know that blue, green, and purple are far enough away on the color wheel from yellow to give me some good contrast, but I also know that the choices have to be fairly dark to offset the hair and the neck. Nothing in my closet is jumping out at me though.
This is frustrating because spring break is almost upon me — so I won’t get any work done next week — and then I only have a short period of time to finish it completely before school is out for summer — and I don’t have any studio time.
I can either use one big piece for the background, something patterned (but not too much — I don’t want it to look like bad wallpaper), or I can use strips — giving a more abstract feel. What to do, what to do . . . . .
The face is so striking and is the “STAR” of the piece…I think just a plain solid for the back…nothing to take away from the face…if you go abstract …think the face will be in a “fight” for attention.
I think this is your best,,, so far! I would tone down the blue so it doesn’t take over, and I’d use black for the background. Love it!!!