Merge pull request facebook#125 from pedsmoreira/patch-1

Add instructions to add to existing projects

Author: kitze

README.md

@@ -21,10 +21,19 @@ The reason for this fork's existence is explained better in [this Medium article
 ### ❔How to use it
 ```create-react-app my-app --scripts-version custom-react-scripts```
 
-Modify the ```.env``` file in the root of the generated project, and add any of the configuration options below 👇 to enable that feature.
+Modify the `.env` file in the root of the generated project, and add any of the configuration options below 👇 to enable that feature.
 
 The generated project comes with every option turned on by default, but you can remove them at any time by removing the options from the ```.env``` file.
 
+#### Adding to an existing project
+
+```
+npm uninstall --save react-scripts;
+npm install --save custom-react-scripts;
+```
+
+Add a `.env.` file with the desired features.
+
 ### 📝 Configuration options
 
 #### Styling