So, people seemed to like the skybox I started on for my contest map. Since it really wasn't that hard to do, here's a little tutorial. This is just getting the image made, once I've figured out how to turn it into a working skybox I'll add it to this post. Results: One thing I forgot to add: If you're aiming to make a skybox out of this you want the image to be huuuuuge, like 4096x2048. So there you have it. I made the tutorial image really quickly so it's pretty rough, but if you spend some time on it you can get a pretty nice image out of it. Edit: Since apparently I didn't make it clear in my original post, you're still going to have to paint over the end result to get a valve-quality texture. Photoshop tricks can only get you so far, eventually you're going to have to do ART.