Remove duplicate instructions from contributing guide

CONTRIBUTING.md

@@ -62,35 +62,7 @@ Have you started using Backstage? Adding your company to [ADOPTERS](ADOPTERS.md)
 
 So...feel ready to jump in? Let's do this. 👏🏻💯
 
-To run a Backstage app, you will need to have the following installed:
-
-- [git](https://git-scm.com/book/en/v2/Getting-Started-Installing-Git)
-- [NodeJS](https://nodejs.org/en/download/) - Active LTS Release, currently v12
-- [yarn](https://classic.yarnpkg.com/en/docs/install)
-
-After cloning this repo, open a terminal window and start the example app using the following commands from the project root:
-
-```bash
-yarn install # Install dependencies
-
-yarn start # Start dev server, use --check to enable linting and type-checks
-```
-
-The final `yarn start` command should open a local instance of Backstage in your browser, otherwise open one of the URLs printed in the terminal.
-
-Depending on the work you're doing, you often also want to run the example backend. Start the backend in a separate terminal session using the following:
-
-```bash
-cd packages/backend
-
-yarn start
-
-yarn lerna run mock-data # Populate the backend with mock data
-```
-
-And that's it! You are good to go 👍
-
-If you need help, just jump into our [Discord chatroom](https://discord.gg/MUpMjP2).
+Start by reading our [Getting Started](https://backstage.io/docs/getting-started/) page. If you need help, just jump into our [Discord chatroom](https://discord.gg/MUpMjP2).
 
 # Coding Guidelines