Retouchers and compositors all agree that selecting and cutting out hair can be a major challenge. It’s even harder when you’re new to Photoshop. With thousands of strands of hair going a hundred different directions, how can you possibly preserve all of that natural variation and detail?

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How to Color Amazing Hair

https://www.udemy.com/course/amazing-hair-color

Up your coloring game! Create amazing effects with colored pencils and see immediate improvement in your coloring style and presentation.
Hair color is a tough subject. Getting hair to look realistic and three-dimensional on a flat coloring page is properly tricky. After taking this course, you will color unbelievable hair with ease.

 How to draw anime hair for Males/ boys

https://www.skillshare.com/classes/How-to-draw-anime-hair-for-Males-boys/1581446389

In this class you'll learn thehair basics and how to draw different hairstyles. and in the last video you're going to know how to darw any hair from reference.

How to Draw Realistic Hair with Colored Pencils

English | 3h 56m | Video 720p

In this class, you will learn to draw realistic hair using colored pencils. You will learn to draw a lot of kinds, styles, and colors of the hair in these simple and practical demonstrations.

How to Paint Straight Hair - Step by Step

English | 19m | Video 720p

This class is for those who want to learn How to Paint Straight Hair.  I will share my complete process step by step which you will be able to follow along easily. I have already published a class on How to paint Curly Hair and you should definitely consider watching it if you want to know. I am going to publish one more class on painting hair which will be for Wavy Hair. To take these classes all you need is a digital art program installed on your device; it can be your PC, Phone or tablet whichever you use will work just fine. And of course you need to have some basic knowledge in digital art. If  you are a beginner make sure to watch my classes for beginners digital artist to get started right away.