Update CONTRIBUTING.md

CONTRIBUTING.md

@@ -5,7 +5,7 @@ We love contributions from our community of users! This document explains our gu
 #### Environment setup
 
 0. Install Node.js (4 or newer) and npm (3 or newer).
-1. Fork Swagger-UI, and clone your fork.
+1. Make a fork of Swagger-UI on GitHub, then clone your fork to your machine.
 2. Run `npm install` in your Swagger-UI directory.
 3. Run `npm run dev`. `localhost:3200` should open automatically.
 4. You're ready to go!