One is located on the rear of the board as shown below.
This one seems better suited to a on board module such a bluetooth or another wifi. The difficultly arises from sources a module that matches the dimensions of the 4 pin layout.
The second port is located on the front side of the board near to the SD card and is easily recognised by the tracing lines for a Type A USB connector.You could try to populate this one with a Type A connector although because the solder pads aren't holed there nothing to keep the connector in place apart from soldering the connector housing to their solder pads.
The next stage was to create a pluggable usb connector, this required a 4 way 0.1" right angle header, a Type A usb connector and a small strip of vero board. I soldered the 4 way header and Type A connector onto the vero board.
Once done I could plug the pluggable usb connector onto the pins on the hackberry using a jump cable made from two 4 way 0.1" female connectors.
Last step was to test it worked, for this I plugged in a usb stick.
When I don't require the usb port I can easily remove the jump cable.