I highly recommend clicking on the image and zooming in wherever you need to. This 'texturing' advice does not only apply to hair.
Who are those characters? At the top left, is the lovely one-eyed brunette, Alex of Kindred of the Carvings. Below her, is 'Richard Plantagenet' of Requiem of the Rose King. To Richard's right, is 'Griffith' of Kentaro Miura's Berserk. Except his hair is reddish-orange, because why not...
Am I qualified to give advice? NO. Is this advice mine? No. I learned this from someone else a while back, and I found it exceptionally useful. So, I'm parroting their genius... in his my own overly complicated way. And hopefully it benefits you.
The Grey Text... What am I talking about? Well, the open, blank spot on the iris edge on the left is a nice visual touch, not necessary. Same goes for the stray hair. The open lips which are not fully enclosed by black lines are more aesthetic. To some people, including me. It's something I learned from the Artist Kentaro Miura, who's work I really like.
Colour advantage... So you may notice the picture on the Left is penciled in, and the one on the Right, is coloured in. I used coloured pencils, prismacolor pencils. I recommend you consider buying some, if you want to. They're great.
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