revert changes to getting started

Author: dburles

packages/docs/src/pages/getting-started/index.mdx

@@ -4,20 +4,13 @@ title: Getting Started
 
 # Getting Started
 
-The `theme-ui` package includes a recommended set of packages out of the box, including [MDX support](/packages/mdx) and a set of [primitive UI components](/packages/components).
-However, if you would prefer a minimal installation, you can instead start with the `@theme-ui/core` package. For more information, see the [core package documention](/packages/core).
-
-## Setup
-
-### 1. Install Theme UI:
+Install Theme UI.
 
 ```sh
 npm i theme-ui
 ```
 
-### 2. Create a theme object
-
-Include custom color, typography, and layout values:
+Create a theme object to include custom color, typography, and layout values.
 
 ```js
 // example theme.js
@@ -41,9 +34,7 @@ If you're using Gatsby, see the [Getting Started with Gatsby](/getting-started/g
 
 </Note>
 
-### 3. Add the theme to your application
-
-Using the `ThemeProvider`, pass in the `theme` object as a prop:
+Add the theme to your application with the `ThemeProvider`, passing in the `theme` object as a prop.
 
 ```jsx
 // basic usage