Or ask the seller for it

Fix one end of the line to the flying saucer.

See if he gave you lead wax.

No, find yourself some scotch tape.

And then the other end is fixed to you.

Stretch the line a little.

The main support point is above the head.

If you can catch it with your ears.

in other words

This line runs overhead.

And fell down.

This can ensure that both hands can move flexibly when the flying saucer rotates.