From Photoshop Layer –Adding Color To A Sketch Image In Photoshop:
Adding color to a sketch image in Photoshop. In this Photoshop tutorial, you are going to learn how to add color to a sketch image in Photoshop. This will allow you to color up your sketches and drawings and give them the neat, finishing touch that you have always wanted. In this tutorial, we are working a bit in the Channels Panel and then in the Layers Panel. Also, there is work to do with saving and loading selections, and with filters and blend modes.