I found inspiration at You Can Make This for this adorable top. I don't remember off hand what size the jeans were that I used, but they were adult & I only used 12" off the bottom of one leg, so loks of parts left to recycle!
I didn't add a neck strap, simply because I think she'll be wearing this over a shirt most times. I made mine reversible
I used this fabric because I made her a headband out of it & they will look cool together!