It is possible to make hair extensions only in the bang zone, but it is necessary to take into account it, s existing length. In case the bangs are short, hair extensions is not appropriate, nothing beautiful will come out of it.
Experience was, at the request of my client, contrary to my recommendations, the service provided. The result is sad, did not live up to expectations.
It is possible to make extension, when the bang grows almost to the chin.
Be patient! Better tolerate and do everything perfectly, rather than quickly and horrible!