Upload the zip file from the gerber directory of the board you'd like to make to a fab house. I use JLCPCB, which is generally cheapest, and quite fast. The default specifications are fine - feel free to change the color, of course!

The 'Components' section lists the part numbers. Take a look at the photos for help in figuring out how many of each component you'll need. For the large fuse board and distribution board, you have the option of using a straight or right-angle connector for the 'in' connector.

You can check Octopart to see part prices from a bunch of common distributors.

Since the large power traces on the PCBs act as giant heatsinks, you'll need to be patient when soldering the components. It'll take longer than usual for everything to heat up enough that solder flows around the entire joint, making a clean connection. I set my iron to about 360C - it's worth experimenting to find the setting that works for you. Too cold and it'll take a long time to solder, but too hot and you risk burning the board or the flux. It takes me about 20 minutes to solder the small fuse board, and 45 minutes for the large fuse board.

If you made one of the fuse boards, you'll need to install fuses. The board takes standard ATC (automotive) fuses. The contacts used on the Anderson connectors support up to 45 amps. I haven't tested the boards under high load, but the large amount of copper means the board should support this. If you do use this high of power, you'll also need to take into consideration the wire gauge that you use - e.g. at 12V 45 amps, with 10 AWG wire (the largest that the Anderson crimp connectors support), you can only use four feet of wire before the voltage drop exceeds 3%. If you use this board with sustained high current, it's a good idea to measure the voltage drop.