So I did some research, found multiple designs and I have combined them in one design, my version isn't fully finished but the plan is all done.
This build is not too difficult, but it requires some technique and experience in the making of chainmail. It will take a lot of time, so don't think of it as a project you could finish in two weeks. if you work on it very well, you might be able to finish it in a month. But it took me longer than that.
Try the coif from time to time, see if it fits. At certain points in this instructable you will need to put it on you head (I know it's very cold but if you put a balaclava underneath it, it's not that bad). If it doesn't fit you, please leave a comment because I hope to help you with it.
For this project, you can use the technique of my other instructable: `A faster way of making chainmail`
Step 1: The coif's plan
The main idea behind this coif, is expansion. You start with a small hexagon and keep expanding it.