GIMP is known as Free Photoshop because he as most, although not all, of Photoshop’s capabilities.

Step 0: Download and Install GIMP from this site: http://www.gimp.org/downloads/

How to choose pen and color

How to use Brush Window

How to read the brightness of each point

How to submit what you did on GIMP into a web-based form such as blog or homework submission page.  This tutorial requires knowledge of Jing.