Added instructions for installation

README.md

@@ -1,6 +1,33 @@
-See the demo [here](http://marvelapp.github.io/devices.css/)
+# Demo
+See the demo website [here](http://marvelapp.github.io/devices.css/).
+
+# Installation
+
+There are two common approaches to use this package in your own application:
+
+## npm:
+
+Run the following command on your console in order to install the package via `npm`:
+
+```
+npm install marvelapp/devices.css --save
+```
+
+This will install the latest version of `devices.css`. However, if you want to specify one particular version, you can run: 
+```
+npm install marvelapp/devices.css#v1.1 --save
+```
+
+whereas `#1.1` may be replaced with your particular version to be installed.
+
+## Download as ZIP:
+
+1. Download the `ZIP` file directly via `GitHub` (see the green `Clone or Download` button!)
+2. Unpack the `ZIP` file  and add manually it to your project.
+3. Follow the instructions below. 
 
 # Usage
-In order to use a device, include devices.min.css at the top of your document and then go back to the [demo](http://marvelapp.github.io/devices.css/) and select the combination you want, and simply copy out the generated HTML. That's it!
 
-This will give you the device you selected, just like we use on Marvel. Use them, tweak them and improve however you want! Also sign up for [Marvel](http://marvelapp.com) if you haven't already because it's pretty good
+In order to display a device, include the `devices.min.css` at the top of your document and then go back to the [demo](http://marvelapp.github.io/devices.css/) website and select the combination you want. Simply copy the generated HTML code. That's it!
+
+This will give you the device you selected, just like we use on Marvel. Use them, tweak them and improve however you want! Also sign up for [Marvel](http://marvelapp.com) if you haven't already because it's pretty good.