It should be noted that this project, to be replicated closely, will require a mill of some sort, along with varying other tools. I will not go into very deep detail on the mechanical creation because everyone has their own methodology. Here are the general steps to follow however.

Download and understand all design files as best as you can. Figure out what you need to order and what you already have, and how to adapt for your specific tools. I used my DIY CNC router that has a 2.2 kW spindle on it, which I highly recommend  if you are currently using a wood router. You could also use a manual mill, with a table saw for the HDPE, but I would not reccomend.

Order as many pieces as possible.

Cut all 8020 (or similar extrusions). I used a miter saw with a roughing blade and WD40. There are better ways to do this however.

Mill components. I used Autodesk's newish (and free!) HSM software coupled with inventor. Made the CAMing worlds easier than my previous workflow (Inventor to DXF to autocad to Cut 2D).

Assemble machine and mount all valves and electronics and route cables.

Assemble electronics from schematic. I reccommend laying everything out first, and then soldering components. Be wary of busses that are tied together on the Proto board.

Load code, install Software on Raspberry pi. (Many places online will demo this). Once I have completed the raspberry pi portion of the project I will creat a turorial for configuring the Pi code.

Go drink a soda, and test the machine out!!