You'll need a board or breakout with a 24-pin connector to use a bare eInk display. There are a few options in the Adafruit shop:

You can also add a cable extender if you want to give your display cable some extra slack:

Hardware Setup

The display ribbon cables plug into the connectors by sliding out the black tabs on the connector, inserting the cable and then pushing the black tabs back in to secure the cable.

Pinouts

Your pinout will vary depending on the breakout or dev board that you choose. 

Feather RP2040 ThinkInk

The Feather RP2040 ThinkInk has the onboard 24-pin connector. It uses these specific pins included as a part of its board definition in both Arduino and CircuitPython:

• EPD_BUSY/GPIO16 - The Busy Detect pin for e-Ink displays. It is available as EPD_BUSY in CircuitPython and PIN_EPD_BUSY in Arduino.
• EPD_RESET/GPIO17 - The Reset pin for e-Ink displays. It is available as EPD_RESET in CircuitPython and PIN_EPD_RESET in Arduino.
• EPD_DC/GPIO18 - The Data Command pin for e-Ink displays. It is available as EPD_DC in CircuitPython and PIN_EPD_DC in Arduino.
• EPD_CS/GPIO19 - The Chip Select pin for e-Ink displays. It is available as EPD_CS in CircuitPython and PIN_EPD_CS in Arduino.
• EPD_SCK/GPIO22 - The SPI SCK pin for e-Ink displays. It is available as EPD_SCK in CircuitPython and PIN_EPD_SCK in Arduino.
• EPD_MOSI/GPIO23 - The SPI MOSI pin for e-Ink displays. It is available as EPD_MOSI in CircuitPython and PIN_EPD_MOSI in Arduino.

You'll use busio to initialize the SPI bus for the 24-pin connector:

• spi = busio.SPI(board.EPD_SCK, MOSI=board.EPD_MOSI, MISO=None)
  

eInk Feather Friend FeatherWing

The eInk Feather Friend is a FeatherWing that has the included 24-pin connector. It uses the following pins when connected to a Feather board:

• SPI MOSI/MISO/SCK
• SD CS to Pin D5
• SRAM CS to Pin D6
• eInk CS to Pin D9
• eInk DC to Pin D10

eInk Breakout Friend

The eInk Breakout Friend is a breakout board that can be connected to any dev board. It has an onboard 24-pin connector and pins broken out along the edge to interface with a connected display.

eInk Bonnet for Raspberry Pi

The eInk Bonnet plugs directly into the 2x20 header on your Raspberry Pi, letting you connect a bare eInk display easily via the 24-pin connector. The following pins are used for interfacing with a display:

• MOSI/MISO/SCK - SPI pins are connected to the default SPI port on the Raspberry Pi.
• CS on Raspberry Pi CE 0.
• DC on Raspberry Pi GPIO 22.
• Reset on Raspberry Pi GPIO 27.
• Busy on Raspberry Pi GPIO 17