How can I earn a rating of 11/10 on Game Dev Tycoon?

That's rather based on luck.

First off, you should know that guide telling a lot about possible matches of topic, genre, audience and system.

  • You should have a good team.
  • Use your boosts at the right time.
  • Develop a sequel of a really successful game (10 rating) to increase your chance of having a 11/10 score.
  • Have luck.

You should also read this wiki article which is really insightful about the game. You can't force a 11/10, you must be patient, and do the right things at the right time to increase your luck.