@Daniel Howse , but I think this source image can produced a better cut with a tiny bit more care.

First of all, have a look at this thread for guidelines for cutters and video tutorials on what we expect for from our cuts.

This is in the wrong dimensions but that's something which can be rectified quite easily.

There is, however, a fair bit of snow around the head. 

There is a very quick and simple method on how to remove it:

However, I suspect that if you use remove.bg, you'd get a better draft cut in the first place. It's a fantastic free online tool which does the heavy lifting for you by removing the background in the source image, leaving you to only rotate, crop and/or nudge the collar upwards. It's tremendously easy to use and provides fantastic quality. With it, you can go from source to cut in a couple of minutes for the vast majority of images.

Here's a couple of videos on how to use it, one when combined with Photoshop and another using photopea.com, which is a free online app so close to Photoshop that it has the same shortcuts, layout and icons 😉 If you don't have Photoshop, photopea.com is the tool I would recommend to use to tweak the draft cut produced by remove.bg. It's more powerful and versatile than GIMP and other similar tools.