I use a programme called paint.net. Its free and there tutorials to help you along. I still haven't got to the level of some of the badges used on that, I just need to practice more. I am really hopeless with computers and all these programes, so if I can do it, honestly, anyone can.
This is the website, you can download from here.
www.getpaint.net/index.html
I am a Norfolk man and i glory in being so
On the bench: Airfix 1/72nd Harrier GR.3/Fujimi 1/72nd Ju 87D-3