WordPress.org

1. Upload the plugin to your wp-content/plugins directory
2. Activate the plugin
3. Embed Flash files using the following syntax.

[flash src="filename.swf" width="500" height="400" /]

You can even get the plugin to show Flash content through widgets, but you have to make a few edits. You just have to edit your themes functions.php and add:

add_filter('widget_text', 'do_shortcode');