Add basic installation instructions

readme.md

@@ -6,6 +6,26 @@ Google Maps field type for [Custom Metaboxes and Fields for WordPress](https://g
 
 The `pw_map` field stores the latitude/longitude values which you can then use to display a map in your theme.
 
+## Installation
+
+You can install this field type as you would a WordPress plugin:
+
+1. Download the plugin ([running an older version of CMB?](https://github.com/mustardBees/cmb_field_map/releases))
+2. Place the plugin folder in your `/wp-content/plugins/` directory
+3. Activate the plugin in the Plugin dashboard
+
+Alternatively, you can place the plugin folder in with your theme/plugin. After you call CMB:
+
+```php
+require_once 'init.php';
+```
+
+Add another line to include the `cmb-field-map.php` file. Something like:
+
+```php
+require_once 'cmb_field_map/cmb-field-map.php';
+```
+
 ## Usage
 
 `pw_map` - Save a location on a map. Example: