What's a good starting point for this project? Learning about PCB design. I've always been a big fan of pulling things apart/ turning them on and playing with it, then reading the manual. I'm doing that with PCBs, and what a better place to start than by downloading the EAGLE files for the Arduino Due? This nets us a fun two layer board design as follows:

So at first look, this looks pretty sweet, but it's a little busy and I'm not digging the ~4 colors for a tattoo. After a quick turning off of the vias and some other things in EAGLE (plus make it monotone), then BAM:

Now that looks much better for a tattoo. At first I wasn't sure how things would work being dual layer, but this isn't too bad. I would like something that the shape would fit the contour of my shoulder/arm better.

If you have any interest in helping out with design or technical input, send me a message. I'm moving forward blind at this point, and I want to document the journey for fun. I'll try to update this as frequently as possible with thoughts and findings.