Ok, so I wanted to create my own textures but I didn't know how and there's no documentation on it. Its actually amazingly simple, although it doesn't seem that way until you know how to do it. So, just so it's written down here it is: First, take a copy of the minecraft.jar file and extract it with WinRAR, depending upon what you want to edit you'll need the terrain, dirt, or GUI.png files. Next, you'll need something to edit it with. The standard paint program that comes with Windows will suffice, but I much prefer paint.net; it's much simpler and much more effective.

Minecraft Texture Map Mac : Minecraft Lego Texture Pack For Mac Free

I will post the download link at the bottom of this tutorial. Finally, open the.png file of choice with the paint.net program and you're free to edit as you please. If there are any questions just post them here.

Link for paint.net download.