You need a Micro-USB to USB-A data cable. The wiki says one is included in the box but there wasn’t one in my box. I already had one. It is common to have Micro-USB to USB-A power-only cables for charging some consumer devices. Power-only cables will not work as a console cable. If you plug it into the board (next to power socket) and your computer and it doesn’t create a serial device on your computer, then it may be the cable. If you use a linux/BSD computer to connect to the console, you will see a serial device created in /dev and probably in your system log. On my FreeBSD machine it created /dev/cuaU0. You will need a profilic USB to serial driver for the serial port emulation to be created. FreeBSD has this driver built-in.