Building kotlin files.

IntelliJ import instructions.

buildJvm/README.md

@@ -20,6 +20,34 @@ Then, run a game
 
 You will need to install openjdk 17, because some games use advanced Java features. 
 We should be using version 17 anyway, because anything less than 17 is deprecated.
+---
+## Using an IDE to work on JVM games
+
+You can open the entire Basic Computer Games project in an IDE, with any IDE capable
+of importing from a gradle project.
+
+### IntelliJ / Android Studio
+
+1. (Optional) If you want to make changes, or contribute a new kotlin or java version
+of one of the games, use [github "fork"](https://docs.github.com/en/get-started/quickstart/fork-a-repo)
+to create your own editable fork of the project.
+2. Check out the code using `File` -> `New` -> `Project from Version Control`
+   1. Enter the URL of the project. For the main project this will be `https://github.com/coding-horror/basic-computer-games.git`, for your
+own fork this will be `https://github.com/YOURNAMEHERE/basic-computer-games.git`
+   2. Choose a directory for the clone to live in
+3. Click `Clone`
+
+The project will open, and eventually you will get a little alert box in the bottom right corner saying "Gradle build script found". 
+
+Click the "Load" link in the alert box, to load the gradle project.
+
+You should see all the games appear on the left side of the screen. If you have loaded
+your own fork, you can modify, commit and push your changes to github.
+
+If you are using the main `coding-horror` branch, you can still make and run your own changes.  If
+your git skills are up to the task, you might even fork the project and change your
+local clone to point to your new forked project.
+
 
 ---
 ## Adding a new game
@@ -37,6 +65,7 @@ The `build.gradle` file will normally be identical to this:
 
     plugins {
         id 'application'
+        // id 'org.jetbrains.kotlin.jvm' // UNCOMMENT for kotlin projects
     }
     
     sourceSets {