The Moon Buggy functions in a similar manner as a boat does in The Overworld, except it requires a solid floor to be placed on and cannot be pushed around. The buggy will always face southward on placement.
Once placed, it can be mounted by pressing the use control on it (right-click) and sneak (default Shift key) to exit the buggy. It may be removed by pushing it (left-click).
To access its inventory and fuel levels, press f. To move around, use wasd keys; the buggy must be fueled to be driven (see fueling below).
The buggy is able to climb and descend over hills and craters on any planet or moon. It is possible to take fall damage while driving the buggy so it is advisable to avoid taking craters head-on at full speed.
Prior to to 1.7.10 version 480, falling from a space station while riding a buggy, or any other vehicle, will glitch the game and the player will die of suffocation in a wall (details on GitHub).
The following materials are required:
It is possible to add storage place in the Buggy. Place Buggy Storage Boxes in the top-right green slots while crafting the vehicle, up to three may be added.
To fuel a Moon Buggy, you must first craft and place a 3x3 area of Buggy Fueling Pads. A Fuel Loader must also be placed adjacent to the Fueling Pad and supplied with fuel. The fuel level can be checked by mounting the Moon Buggy and pressing the F key.
Breaking the vehicle will not cause it to lose its fuel.
Lunar Roving Vehicle article on the Wikipedia.