https://www.sdcard.org/downloads/formatter_4/eula_mac/index.html
For Windows based machines, use this:
https://www.sdcard.org/downloads/formatter_4/eula_windows/index.html
Agree to the licensing requirements, download the application and install on your computer. Follow the instructions. It is recommend to use the full reformat option to FAT 16.
For SD card types and specifics, please refer to this: https://www.psaudio.com/ps_faq/sd-card-questions/