Download the brd file. Before you send it off to be made, find a Pro Mini source. Not all of them have the same footprint so match the two.

The board uses 0603 capacitors. It could easily enough be changed to bigger, and probably even PTH so figure out which route you want to go and get the parts. You'll need 2x 1uF and 1x 100uF caps. 

Get the transistor. It's a tiny little thing. PTH versions are available. 

Get a USB connector. I got these, and you'll notice the footprint doesn't exactly match to the brd file. To make sure it all works, you'll need to pull out the middle wires of the connector. If they happen to get soldered together, you'll blow the transistor, so I just twisted and pulled them out. 

Put the board together. Put a 1uF cap on both sides of the transistor and add the 100 uF cap after the USB connector.

Now you've got a board, the Pro Mini, and the nrf24 boards. You need to solder the nrf24 onto the board now. You don't need to keep the plastic spacer of the nrf24 on, but make sure to put a few strips of electrical tape on the back if you do. The boards have a PTH crystal that will short the board below it. And oddly enough, it will still halfway work, it just won't Tx (very tricky). 

You can put the board and pro mini together with these. Or you can do it your own way. You will have to trim one side of the headers if you do what I did to give the radio module room. (You'll see what I mean). At a minimum, you must connect the pro mini pins 9 - 13 to the board along with the VCC and GND that the board connects to. This part is sort of like a puzzle, figuring out what to solder together first. 

Upload the software using an FTDI programmer and that's it.