Once the weighted section is noticed keep your same eye on it and pick the heavy section up with your hands and get ready to comb it through and either point cut or get your thinning scissors ready to make your snip. The best technique I've found when it comes to removing weight from bangs or a fringe is to get the client to look in the mirror and your best hairdressing eye should be able to see where the density of the hair is falling creating a heavy fringe. It's the first damn thing we see on the face, so if it doesn't look right then well good luck to you! Not always do you need to remove weight from bangs but when you do, it must be done with absolute care.