I just use some Loctite Super Glue in the bottle with little brush. I just dab a little on where I will place the eye. I pick it up with the point of my bodkin and place it down and push with blunt end of bodkin. After that and once dry I like to put a clear coat of Vinyl over the entire head including the eyes, but last strp is not really necessary after it's glued on well. It does look better with the vinyl over coat though. As far as best, I am unsure of that.
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