Back from school now so... And yes this is from the tutorials thing I shown you.
Open paint.net.
Then click on the gradient tool.
Use the linear one(it is shown as a Black to white image).
And then make it so its got black on the top and white of the botton.
Now make a new layer... (ctrl+shift+N)
Click on effects then clouds. And now duplicate the cloud effect easily by pressing Ctrl+F. And do this a dozen times till you see it have a firey look. Now click on the curves tool. By going to... Adjustments>Curve.
Now click on RGB. By clicking on the Luminostity button. And it should say RGB on top.
Now if done right you should do this on the curve menu.
Now click on the layer with the clouds on and then change the blending option to multiply. Now if you want you can fiddle with it for awhile and make even more awesome stuff! You can even make Blue fire!Sorry for the lack of images I just got back from school. Next will be a how to use Blenders Uv mapper.
Not a paint.net tutorial but it will help out alot of people who use the Uvmappers that are completely different programs.
[href]http://www.freewebs.com/deatheadstudios/
[/href]