Write ScreenlyOS to a microSD card, update the bootloader, assemble a player from parts, and fix the problems that come up while flashing.
Writing ScreenlyOS to a card takes a few minutes. Most of the time that is all there is to it.
If the board is a Pi 4 or Pi 5 that has never been updated, do the bootloader first, because a board with an old bootloader will not start ScreenlyOS however cleanly the card was written.
Write ScreenlyOS to a microSD card with the Raspberry Pi Imager, or with any flashing tool from a downloaded image, and pair the screen.
Fix a Raspberry Pi 4 stuck on a white screen or a Pi 5 on a blinking cursor by updating the EEPROM bootloader, using the Raspberry Pi Imager or the terminal.
The card reporting the wrong size, a card that will not format, and a Pi that will not boot after writing ScreenlyOS.
The parts you need to assemble a Raspberry Pi into a ScreenlyOS player, which case and power supply to choose, and how to put it together.