The Satan Inside stickers are available as a
Postscript file you can download.
They were designed to be printed on 1.25" round yellow glow stickers
that come 15 on a page in a 3x5 layout, specifically Avery #05499.
The sticker sheets are only about 4x6", so can't go through some laser
printers. I use an HP4MP which can handle them. Of course, you can
always modify the layout. I think Avery also makes 8x11" size
sheets of the stickers, although they are more expensive.
The sticker was created using the physical cut and paste method
from actual printed logos of a similar variety. The "a" was made
by cutting the top off the "d". All the other letters already
existed. The resulting physical prototype was then faxed from
a fax machine to a fax modem in order to scan it in (sorry didn't
have Photoshop or a scanner back then). The result is a bit
ragged but adds a nice effect that I like a lot.