Uploading code
There are not a lot of differences between an ESP32 DevKitC and the ESP32 TouchDown when it comes to uploading code. That means that you can select an ESP32 DevKitC when uploading. There is an auto-reset circuit on the board, so you do not need to press any buttons, just hit upload and the board will do the rest.
Note: Sometimes the ESP32 doesn't go in to upload mode by itself. Pressing the "Boot" button should start the upload.
Board settings in the Arduino IDE:
If you want, you can add the ESP32 TouchDown to the Arduino IDE board manager so that the ESP32 TouchDown shows up as a separate board. You can do this by appending the contents of the boards.txt from this repository, to the boards.txt of you Arduino IDE installation. You can find the boards.txt file in the Arduino15 folder, under /packages/esp32/hardware/esp32/<the ESP32 release you have>
This step is however not needed:
The USB to serial interface is a CP2102 by Silicon Labs. Drivers for this should automatically install. But if this is not the case, you can find them here: CP2102 Drivers
*Note on MacOS Big Sur, there was an issue with the drivers. This should be fixed as of v6.0 (12/22/2020) of the MacOS drivers.