minor formatting

README.md

 # Presentation slides
 
-## how to get started
+## How to get started
+
+```bash
+$ npm install -g npm@latest grunt-cli generator-reveal
+$ npm install
+```
+
+## How to develop locally
 
 ```bash
-$ yarn install
 $ grunt server
 ```
 
-## how to publish
+## How to publish
 
 ```bash
 grunt dist
-```
\ No newline at end of file
+```