From main menu choose:
Academy>Venue Creator>Create New Venue
Open the Tool Kit (default X on keyboard), select Courts then select any of the courts (it can be either Main, Show or Outer) and drag and place the court.
Repeat 7 times, you should have had 7 courts placed. After that, exit using ESC, pop up will appear asking if you want to save.
Choose yes and you will get achievement.