StarliteBlack Basic Leather Ballet Shoes

I have received the shoes, what are you suppose to do with the loose elastic on each shoe?

Why is the elastic only attached to one side of the shoe???

I was wondering my child is size 5 should i get size 6 ? and if so which one is the right option as they have child and adult all mixed up in the opti

My daughter wears a size 6 adult shoe - what size should I go for?