Now the fun part! Choosing where you want to have your boards made. Adafruit does not endorse any particular manufacturers and browsing through guides that make boards, different companies are used. It is your choice. There are several companies in China, in the US, and in Europe. 

For this project, I specified OSH Park in the US. That provides closer geographic manufacturing but puts constraints on what can be manufactured. OSH Park's standard solder mask is purple and silkscreen white. Sending them to other manufacturers often provides more choices.

OSH Park only imports KiCad 6 and earlier, not KiCad 7 (as of this guide being first released). Therefore the Zip file of Gerbers and Drill files is needed.

I pressed the Browse for Files button and selected the Zip file. If everything has gone well, they will show you the design. They charge $5 for 3 boards of 1 square inch each (You cannot order just one board). That is fine, I want two for earrings and one for a pendant.

If the manufacturer finds issues that need resolving (like no drill files found), they'll tell you.

Some manufacturers will allow you to specify the solder mask color and possibly the silkscreen color at this point.

Provide your payment information, contact information, and how fast you want the boards. I paid extra for "speedy service". The company will then provide confirmation and often tracking information as the manufacturing process proceeds.

Receiving Your Boards Back from the Manufacturer

Here are the boards as received from OSH Park. Beautiful! The outside ones are on the front side, and the center one is flipped over to the back (showing the hole mirrored). 

Notice the little bits on the edges. Sometimes called mouse bites, they are the remnants of the connections between boards when the large panel was laid out.

You can use a rotary tool with proper eye/lung protection to remove the excess but there is a risk of removing too much. For these small ones, I'll use a file carefully.