docs(getting-started): revise docs (#3523)

* docs(getting-started): revise docs

* minor changes

Author: andrewseguin

guides/getting-started.md

@@ -1,45 +1,44 @@
-Get started with Angular Material using the Angular CLI.
+For help getting started with a new Angular app, check out the [Angular CLI](https://cli.angular.io/).
 
-## Install Angular CLI
- 
- ```bash
- npm install -g @angular/cli
- ```
- 
-## Create a new project
- 
- ```bash
- ng new my-project
- ```
-
-The new command creates a project with a build system for your Angular app.
+For existing apps, follow these steps to begin using Angular Material.
 
-## Install Angular Material components 
+## Step 1: Install Angular Material 
 
 ```bash
 npm install --save @angular/material
 ```
 
-## Import the Angular Material NgModule
+## Step 2: Import the Module
+  
+Add MaterialModule as an import in your app's root NgModule.  
 
-**src/app/app.module.ts**
 ```ts
 import { MaterialModule } from '@angular/material';
-// other imports 
+ 
 @NgModule({
+  ...
   imports: [MaterialModule],
   ...
 })
 export class PizzaPartyAppModule { }
 ```
 
-## Include the core and theme styles:
-This is **required** to apply all of the core and theme styles to your application. You can either
-use a pre-built theme, or define your own custom theme.
+## Step 3: Include Theming
+
+Including a theme is **required** to apply all of the core and theme styles to your application. 
 
-:trident:  See the [theming guide](./theming.md) for instructions.
+To get started with a prebuilt theme, include the following in your app's index.html:
+
+```html
+<link href="node_modules/@angular/material/core/theming/prebuilt/indigo-pink.css" rel="stylesheet">
+```
+
+Note that your app's project structure may have a different relative location for your node_modules.
+
+For more information on theming and instructions on how to create a custom theme, see the [theming guide](./theming.md).
+
+## Step 4: Gesture Support
 
-### Additional setup for gestures
 Some components (`md-slide-toggle`, `md-slider`, `mdTooltip`) rely on 
 [HammerJS](http://hammerjs.github.io/) for gestures. In order to get the full feature-set of these
 components, HammerJS must be loaded into the application.
@@ -48,42 +47,45 @@ You can add HammerJS to your application via [npm](https://www.npmjs.com/package
 (such as the [Google CDN](https://developers.google.com/speed/libraries/#hammerjs)), or served 
 directly from your app.
 
-#### If you want to include HammerJS from npm, you can install it:
-
+To install via npm, use the following command:
 ```bash
-npm install --save hammerjs 
+npm install --save hammerjs
 ```
 
-After installing, import HammerJS on your app's module.
-**src/app/app.module.ts**
+After installing, import it on your app's root module.
 ```ts
 import 'hammerjs';
 ```
 
+## Step 5 (Optional): Add Material Icons
+
+If you want your `md-icon` components to use [Material Icons](https://material.io/icons/), load the font in your `index.html`.
+  
+```html
+<link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
+```
+
+For more information on using Material Icons, check out the [Material Icons Guide](https://google.github.io/material-design-icons/).
+
+Note that `md-icon` has support for any font or svg icons, so using Material Icons is just one option.
+       
+
 ## Configuring SystemJS
+
 If your project is using SystemJS for module loading, you will need to add `@angular/material` 
 to the SystemJS configuration:
 
 ```js
 System.config({
   // existing configuration options
   map: {
-    ...,
-    '@angular/material': 'npm:@angular/material/bundles/material.umd.js'
+    ...
+    '@angular/material': 'npm:@angular/material/bundles/material.umd.js',
+    ...
   }
 });
 ```
 
-### [Optional] Using Material Design icons with `md-icon`:
-
-- If you want to use Material Design icons in addition to Angular Material components, 
-load the Material Design font in your `index.html`.  
-`md-icon` supports any font icons or svg icons, so this is only one option for an icon source.
-       
-**src/index.html**
-```html
-<link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
-```
 
 ## Sample Angular Material projects
 - [Material Sample App](https://github.com/jelbourn/material2-app)