site: improve instructions for using local copy of Svelte

site/README.md

@@ -13,7 +13,11 @@ Start the server with `npm run dev`, and navigate to [localhost:3000](http://loc
 
 ## Using a local copy of Svelte
 
-By default, the REPL will fetch the most recent version of Svelte from https://unpkg.com/svelte. To use the local copy of the compiler and runtime from this repo, you can navigate to [localhost:3000/repl?version=local](http://localhost:3000/repl?version=local). To produce the proper browser-compatible UMD build, you will need to run `npm run build` with the `PUBLISH` environment variable set (to any non-empty string).
+By default, the REPL will fetch the most recent version of Svelte from https://unpkg.com/svelte. When running the site locally, you can also use your local copy of Svelte.
+
+To produce the proper browser-compatible UMD build of the compiler, you will need to run `npm run build` (or `npm run dev`) in the root of this repository with the `PUBLISH` environment variable set to any non-empty string.
+
+Then visit the REPL at [localhost:3000/repl?version=local](http://localhost:3000/repl?version=local).
 
 ## REPL GitHub integration