Add bootstrap path example to installation

docs/guides/installation.md

@@ -50,6 +50,20 @@ tk bootstrap <GIT-PROVIDER> \
 If you wish to install a specific version, use the toolkit 
 [release tag](https://github.com/fluxcd/toolkit/releases) e.g. `--version=v0.0.14`.
 
+With `--path` you can configure the directory which will be used to reconcile the target cluster.
+To control multiple clusters from the same Git repository, you have to set a unique path per
+cluster e.g. `staging-cluster` and `production-cluster`:
+
+```sh
+├── staging-cluster # <- path=staging-cluster
+│   └── gitops-system # <- namespace dir generated by bootstrap
+│       ├── toolkit-components.yaml
+│       ├── toolkit-kustomization.yaml
+│       └── toolkit-source.yaml
+└── production-cluster # <- path=production-cluster
+    └── gitops-system
+``` 
+
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