What I’ve found is that there is no single, simple method that will work for selecting hair. What I have come up with is a method that will work under all circumstances. It is a bit tedious, though. Most of my pictures didn’t have a nice clean background. That made creating a mask difficult.
This was typical. Notice that it’s not easy to even see the hair.

Whatever it takes so that you can easily see the hair. Here, I just used the Shadows/Highlight image adjustment. Because there is such a complex back- ground, I left the image in color. Some people like to desaturate the image or use channel mixer. They didn’t work for this image.

Use the lasso tool to create a selection inside the figure. Use Edit/ Fill to fill the selection with white. In masks, remember that “white reveals and black conceals.” You could also use the Filter/Extract tool to create the selection.

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