| | Re: There are gaps in my woven headbands...
Experiment to see what the real issue is--cover the underside with a piece of felt or tape to hide the teeth and see if the result is the same. I*f so, then you know it's not the teeth. Teeth are usually pretty small and in my opinion should not cause large gaps.
Push up and use clips to hold as was suggested. That helped me when I was first learning.
If those don't help, then it's the width of ribbon to headband size ratio. Vary the size of your headband and see if that helps.