WordPress.org

First time

1. Copy the directory auto-delete-posts to your /wp-content/plugins directory.
2. Go to 'Plugins' under the Administration menu and Activate the plugin.
3. Go to 'Settings->Auto Delete Posts' to view the current configuration.
4. Modify options, enable plugin and UPDATE.

You're done.

Upgrade (pre v1.2)

1. Update the plugin, activate, deactivate and re-activate the plugin to remove configuration frmo previous versions.
2. Choose the appropriate action and set the expiration days.

Upgrade (post v1.2)

1. Upgrade the plugin.
2. Choose the appropraite action and set the expiration days.

If everything looked good, you're done.