Add the moto:bit
Before you snap in the moto:bit board, insert your micro:bit into the moto:bit as shown here.
The moto:bit snaps into the lowest of the notches on the moto:bit Mounts (G). Make sure the power jack is facing
the left side of the robot. Push gently and evenly until it snaps into place.
Note:
The other slots in the moto:bit mounts can be used to hold the Arduino Uno or the Sparkfun RedBoard.
Once snapped, your setup should look like the image below without the wires connected to the moto:bit board