Update README.md

README.md

@@ -16,7 +16,7 @@ Before using this SDK, register your application on the [Uber Developer Site](ht
 The Uber Rides iOS SDK is a CocoaPod written in Swift. [CocoaPods](http://cocoapods.org) is a dependency manager for Cocoa projects. You can install it with the following command:
 
 ```bash
-$ gem install cocoapods
+$ sudo gem install cocoapods
 ```
 
 To integrate Uber Rides into your Xcode project, navigate to the directory that contains your project and create a new **Podfile** with `pod init` or open an existing one, then add `pod 'UberRides'` to the main loop. If you are using the Swift SDK, make sure to add the line `use_frameworks!`.