開発において必要な内容をGET_STARTED.mdに記載

docs/GET_STARTED.md

@@ -1 +1,53 @@
 ## Get Started
+
+### Advance preparation
+
+- Install the IDEs.
+    - [IntelliJ IDEA], [Android Studio] or [Visual Studio Code]
+    - [Xcode]
+- Enable the [fvm] command.
+- Enable the [melos] command.
+
+### Set up Flutter SDK
+
+```shell
+fvm use
+```
+
+### Set up the IDEs to use fvm
+
+If you use [Visual Studio Code], already set up.
+
+If you use [IntelliJ IDEA] or [Android Studio], please see the following document:
+
+https://fvm.app/docs/getting_started/configuration#android-studio
+
+### Install dependencies
+
+```shell
+melos bootstrap
+```
+
+### Run app
+
+The run-configurations are set up to run this app.
+
+Please check:
+
+- `.vscode/launch.json` for [Visual Studio Code].
+- `.idea/runConfigurations/~.xml` for [IntelliJ IDEA] or [Android Studio].
+
+
+<!-- Links -->
+
+[IntelliJ IDEA]: https://www.jetbrains.com/idea/
+
+[Android Studio]: https://developer.android.com/studio
+
+[Visual Studio Code]: https://code.visualstudio.com/
+
+[Xcode]: https://developer.apple.com/xcode/
+
+[fvm]: https://fvm.app/
+
+[melos]: https://melos.invertase.dev/