I started this little project with little more than a dream of making a silly toy actually do something useful for us nerds. The first version I made had 1-20 on one side and 1-10 on the other. I decided to shoot the moon and get 6 different dice sets of numbers on it when I re-designed it.
Step 1: Designing the Dial
To start with, I designed the dial for each side using Excel tables. (This is also why all of the numbers are facing the same direction) It's a complicated table, but not difficult to work out. From there I took screenshots of each side and made svg files out of them. (There's tutorials and free services out there to help with this)
Step 2: Design in Tinkercad
Once I got a good set of svg files I imported them into tinkercad and used them to make holes in a cog design. The most important thing to do when making a spinner is get the sizing right. Standard 608 bearings (this is what almost all spinners use) require a 22mm hole to be pressed into and the thickness of your design should only be 7mm.
Step 3: Design a Cap
You can either design a cap for your spinner, or do like I did and modify a cap style you like to make yours. I found one that I really liked and modded it to make the custom one you see in my pictures. The original design can be found here (https://www.thingiverse.com/thing:2320555) I highly recommend his design as a starting point for designing quality caps.
Step 4: Get to Printing
Here it is, the final step. Load the files in your slicer and print them out.