Monorepo README updates

README.md

@@ -22,25 +22,42 @@ The Primer CSS repo is managed as a monorepo that is composed of many npm packag
 
 This repository is distributed with [npm][npm]. After [installing npm][install-npm], you can install `primer-css` with this command.
 
-```
+```sh
 $ npm install --save primer-css
 ```
 
 ## Usage
 
-The source files included are written in [Sass][sass] (`scss`) You can simply point your sass `include-path` at your `node_modules` directory and import it like this.
+The source files included are written in [Sass][sass] (SCSS). You can point your Sass `include-path` at your project's `node_modules` directory and import it like this:
 
 ```scss
 @import "primer-css/index.scss";
 ```
 
-You can also import specific portions of the module by importing those partials from the `/lib/` folder. _Make sure you import any requirements along with the modules._
+You can import individual Primer modules by installing them each with npm, for instance:
 
-## Build
+```sh
+$ npm install --save primer-navigation
+```
 
-For a compiled **CSS** version of this module, a npm script is included that will output a CSS version to `build/build.css` The built CSS file is also included in the npm package.
+Then, you would import the module with:
 
+```scss
+@import "primer-navigation/index.scss";
 ```
+
+Or, while you're figuring out which modules you need, you can import them directly from the `primer-css` [`packages` directory](./packages) like so:
+
+```scss
+@import "primer-css/packages/primer-navigation/index.css";
+```
+
+
+## Build
+
+For a compiled **CSS** version of this module, an npm script is included that will output a CSS version to `build/build.css`. The built CSS file is also included in the npm package.
+
+```sh
 $ npm run build
 ```