The PI Radio Case was designed to create a small, easy to use radio with decent sound. It uses the PhatBeat header from Pimoroni (its great), which can either be purchased alone or as as part of a Pi Radio kit, full links are below. It will of course work with any other audio output from a Raspberry Pi Zero.
The speaker has been replaced with a Surface Transducer, allowing a smaller case as well as making use of what ever surface the radio is placed upon to enhance the sound. The transducer is at the bottom of the unit as a small metal disc, placing it on a wooden surface creates the deepest sound, a sound beyond the size of the device.
The buttons are 'mini arcade' buttons, aimed at simplifying the operation of the radio - it features play/pause (Yellow), next station (Blue) and Volume up (Red), Volume Down (Green). There is no power off in the current version as its built to be left powered for instant audio (although the feature is built into the PhatBeat so can be easily extended). The wiring is as per the PhatBeat output pins. See the Radio Kit for the full software install and full details on how to get the radio working.
To allow the buttons to be wired, a stacking header is used on the Phatbeat - providing easy access to the GPIO pins:
PhatBeat - https://shop.pimoroni.com/products/phat-beat
PhatBeat GPIO Pins - https://pinout.xyz/pinout/phat_beat
Surface Transducer from https://shop.pimoroni.com/products/surface-transducer-large?variant=7549052353&gclid=EAIaIQobChMIt_rwhoqJ4AIVLrvtCh1TNg9bEAQYASABEgI-0fD_BwE
Radio Kit - https://shop.pimoroni.com/products/pirate-radio-pi-zero-w-project-kit
Mini Arcade Buttons . - https://shop.pimoroni.com/products/mini-arcade-buttons
Youtube clip https://youtu.be/BSZwm-QcnEU
Blog post on the radio at http://www.digitalurban.org/2019/01/raspberry-pi-internet-radio.html
Print the radio case so the open end is pointing upwards - you should be able to print it without supports.