.. How to clean the mirror?

Toni has probably trained you well. You need some cloth and cleaning liquid.

Booze would be quite good for removing dirt.

Doc has the booze bottle. He promises a sip for you.

Yes, and you left a surprise for him to the bottle. Clean the bottle.

There is a Cloth in the Control Room. That should suffice.

Use it on the bottle. The bottle is now clean and the cloth is soaked with alcohol.

You were cleaning the mirror, remember? You can now clean the mirror with the soaked cloth.