Updated README instructions

README.md

@@ -1,6 +1,5 @@
 # Tweeter Totter
 
-
 ```
 🦜           🦜
 --____--______--
@@ -9,10 +8,22 @@
 
 Keep your Twitter tweet-to-follower ratio in check.
 
+## Getting setup
+
 You will need to create credentials for your app at [developer.twitter.com](https://developer.twitter.com) and create a hidden JSON file in your home directory at for your operating system:
 
 - Windows: `/home/<USERNAME>/.tweeter-totter.json`
 - Mac: `/Users/<USERNAME>/.tweeter-totter.json`
 - Linux: `/home/<USERNAME>/.tweeter-totter.json`
 
-Look at the `credentials-example.json` file in this repository to see how it should be structured.
+Look at the `credentials-example.json` file in this repository to see how it should be structured.
+
+## How to use
+
+Once you've setup your credentials you can run Tweeter Totter:
+
+`node bin/tweeter-totter.js`
+
+If you'd like to install it globally so that you can simply invoke `tweeter-totter` from anywhere you can do so like this:
+
+`npm install -g`