How do you set a value in the IntelliJ Registry?

If you are using OS X, you can open the registry by typing 'cmd + shift + A'. Type 'registry' and change the value of the option you're looking for. In this source you can see an example.

Press Ctrl-Alt-Shift-/ and select "Registry" from the menu that appears.

(If that keyboard shortcut is not working for you, use your configured keyboard shortcut for Find Action. On Mac by default it is Shift+⌘+A, on Windows it is Shift+Ctrl+A (docs). Then type "Registry" and click or hit enter.)