Update the README to point to JetBrains documentation where appropriate.

Fixes #1136

PiperOrigin-RevId: 666125973

Author: plumpy

README.md

@@ -35,23 +35,24 @@ is available from the plugin repository. To install it, go to your IDE's
 settings and select the `Plugins` category. Click the `Marketplace` tab, search
 for the `google-java-format` plugin, and click the `Install` button.
 
-The plugin will be disabled by default. To enable it in the current project, go
-to `File→Settings...→google-java-format Settings` (or `IntelliJ
-IDEA→Preferences...→Other Settings→google-java-format Settings` on macOS) and
-check the `Enable google-java-format` checkbox. (A notification will be
-presented when you first open a project offering to do this for you.)
+The plugin will be disabled by default. To enable,
+[open the Project settings](https://www.jetbrains.com/help/idea/configure-project-settings.html),
+then click "google-java-format Settings" and check the "Enable
+google-java-format" checkbox.
 
-To enable it by default in new projects, use `File→Other Settings→Default
-Settings...`.
+To enable it by default in new projects,
+[open the default settings for new projects](https://www.jetbrains.com/help/idea/configure-project-settings.html#new-default-settings)
+and configure it under "Other Settings/google-java-format Settings".
 
 When enabled, it will replace the normal `Reformat Code` and `Optimize Imports`
 actions.
 
 #### IntelliJ JRE Config
 
 The google-java-format plugin uses some internal classes that aren't available
-without extra configuration. To use the plugin, go to `Help→Edit Custom VM
-Options...` and paste in these lines:
+without extra configuration. To use the plugin, you need to
+[add some options to your IDE's Java runtime](https://www.jetbrains.com/help/idea/tuning-the-ide.html#procedure-jvm-options).
+To do that, go to `Help→Edit Custom VM Options...` and paste in these lines:
 
 ```
 --add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED