As a Demon Marshal-level being, Xiaoqing could fly into outer space on her flying sword, reaching the moon at a speed faster than a rocket, continuously accelerating using her extraordinary powers.
In fact, it took her just over twenty hours to reach the moon; she spent most of the time watching TV dramas on her computer while flying.
If she wasn't afraid of colliding with some meteorite in space, she could have flown even faster. At her current speed, even a collision wouldn't hurt her.
After arriving on the moon, she descended to a particularly sturdy mountain range, dug a hole, then carved out a vast space inside and set up an Array to ensure its stability, so it wouldn't collapse for any reason. Next, she installed a door for sufficient sealing and arranged Arrays to produce oxygen and regulate air pressure.
Then she created a magic water source and a set of magic lights.
