can somebody help me with a video or explanation or a youtube video about how to make a chin protection flap for a zip to a jacket. It is ok till the point that I sew on one of the front part, under the zip, but on the top, I have to turn over about 3 cm, like that that the zipper stays between. I can not succeed to do it. I tried in every way and is not ok. I will try to attach some picture that you understand better. Please help, because I am going crazy.