The first step was inserting the shapes, with it being made of circles and a square. Then, I made one larger circle, a medium circle, and finally a smaller circle. Then, I subtracted the smaller circle from the larger circle.

Now, I use a box to subtract half of the circle. Lastly, I made two squares in the large circle; these will hold the half circle.

For this, I used black acrylic but would recommend using wood as this was very hard to glue and does not feel glued that well. Or, you may use superglue rather than craft glue.

Now it's time to laser. I used my S1, but if you only have an F1 Ultra, you should be able to cut this with the diode laser. However, I prefer using a more powerful machine. Just remember your laser safety glasses.

For this, you will glue the half-circle onto the circle. Then, you will need to attach a keychain. Here is the one that I used from Amazon: https://www.amazon.com/dp/B00XWIY7WO

Good news, you're done! I did not glue my reminder to the cap but rather used a Command strip.