NOTE: This article is still in progress. It will be extended & updated step-by-step.
This article will get you an overview on how to make your own Arduino board, even if you are not into electrical engineering.
Step 1: Build a rough prototype
If you have just an idea or even a detailed concept, try to build a first prototype. Regardless if it is bulky or even looks awful at first, it might help you to get a feel of how this thing should work and most important if it works at all.
Arduino Uno (or similar) and a standard breadboard will work just fine. If you already want to go smaller, there are plenty of smaller Arduinos and Arduino-campatible boards, like the Arduino Pro Mini or Micro, the Pro Micro from Sparkfun or the various Feather boards from Adafruit.
Step 2: Modify your prototype, create breakout boards!
Maybe you are still missing a component that is not available or you want to use a similar component which you can’t buy broken out?
In our case, we had a breakout board for an accelerometer but we needed a different one. So we decided to make a breakout board for this specific sensor at first for testing and verifying its features.
The positive aspect about creating a breakout board is that you get to know the layout software, you build a board from scratch and go through the whole process without the need for complicated schematics etc.
Read your component’s datasheet to get the required pinouts, optional components and wiring needed.
Step 3: Make yourself familiar with a layout software
Most Arduino(-compatible) boards provide the source files of layout (.brd) and schematics (.sch) in a format that was made with the EAGLE layout software. Technically you don’t have to rely on that specific layout software, but many open source manufacturers currently use it, so it will be the best choice for now and it’s freeware for makers and students (non-commercial).
You could also craft your boards with Fritzing, as it is a user-friendly software for getting started with hardware layout. A big advantage using Fritzing is that you can directly order your PCB for a really good price – great for prototypes or small production runs (based in Germany/Berlin).
Step 4: Start creating your own board
Now that you may be familiar with the basics of your layout software, we will create our own board.
Whether you need compact dimensions, a specific microcontroller or clock speed: In most cases you will save a vast amount of time and struggle, if you build on existing hardware layouts or at least get insights from existing schematics. It just will speed up your work and even your learning curve.
If you already experimented with a similar board while prototyping, then you can use the layout files and schematic (if available) as a starting point for your board and rework the file to meet your expectations.