It's fairly easy, actually. The only thing you need is Photoshop and about 20-9001 minutes (depending if you're good or not).
Firstly, I used the "clone stamp tool" to remove Skeletron and the text.
Secondly, I cut the billboard out, just to keep it for later, so I could place it over the re-added picture, just with a lower opasity so it would get the old bilboard paper effect from the original picture.
And thirdly, I placed a random picture which I had in my "pictures" folder, and I then proceeded to make it 3d and wrap it around the edges of the billboard. This is when the "billboard paper effect" comes it. I basically just placed it over the picture which I had added, and then it ended up looking like this.

It's late, and I've got nothing better to do.

....Skeletor....

fuck yeah!

It's beautiful

who she be?

No specific source, googled it up a bit and was actually made based on Dungeon Master from the old Dungeons and Dragons cartoon, here's source on dA, and bellow colored source.

matsu-sensei.deviantart.com/art/It-s-magic-213188110
matsu-sensei.deviantart.com/art/Colorful-magic-213460388

Uh....Magic Tits McGee. I don't know.