Model the hero's collar

Hi!
I need help to modeling shirt collar of 3d model of Kyashan.


I have the neck e lower vertices, now I dont know how get this shape:
image

Could someone give me a hand or a suggestion?

Thank you

If you create a loop where the collar starts, you can extrude that up and manipulate the verts and edges to create that shape.

Ok I realized what I was wrong.
I extrude along Z
I apply the mirror
I Scale along X and Y
With the mirror modifier active, I only got bad results.
I am now very close to my goal

Another thing I realized is that in the reference photo, the character doesn’t have a shirt-style collar, but he has a kind of very short cape.
A barely hinted cloak.

So I will do other tests to experiment and gain experience.

Thanks for the help