docs: notify deps install to build book
@@ -4,9 +4,10 @@ The kubebuilder book is served using [mdBook](https://github.com/rust-lang-nurse
1. Follow the instructions at [https://github.com/rust-lang-nursery/mdBook#installation](https://github.com/rust-lang-nursery/mdBook#installation) to
install mdBook.
-1. cd into the `docs/book` directory
-1. Run `mdbook serve`
-1. Visit [http://localhost:3000](http://localhost:3000)
+2. Make sure [controller-gen](https://pkg.go.dev/sigs.k8s.io/controller-tools/cmd/controller-gen) is install in `$GOPATH`.
+3. cd into the `docs/book` directory
+4. Run `mdbook serve`
+5. Visit [http://localhost:3000](http://localhost:3000)
# Steps to deploy
