Yes, we meant "on": You sat on top of the damn thing. There were no walls, no ceiling. Just a chair, you and open space.
"Look, it says right here in the manual: You have to hold my hand if I ask."
Once you were belted into your hastily assembled rocket chair filled with stolen fuel, you simply aimed for that tiny glimmer of light in between the stars. That was your Command Module. It's been up there the whole time, orbiting the moon, ready to take you home. All you have to do is hit it ... exactly.
It's like threading a needle that's a mile away and made of burning death.
This was accomplished using math and explosions and little else: The computer was deemed "too heavy" to be necessary, so it was up to the copilot to run all the calculations on a scratchpad, trying to work out the precise trajectory of both the LESS and that pinprick of light miles up in space. And if he forgot to carry a 1 and delayed the pickup by a few hours, then you both died in a vacuum. Because the LESS had no life support systems, aside from the four hours of air in the suit's backpacks, much of which would likely be used in the preparation stages. If literally anything went less than perfectly -- if one external variable went wrong, or if any component failed -- two astronauts went hurtling off into the blackness of space on the worst Bungee Chair Ride in history.