When using /sample-post/ or /%postname%/ permalinks and a slug consisting of only numbers, WordPress incorrectly interprets this as pagination and doesn't handle things correctly. This plug-in will send users to the correct post.
The best way is always to install through the WordPress back-end.
If you want to do it manually:
- Upload the
numeric-slugs directory to the /wp-content/plugins/ directory.
- Activate the plugin through the 'Plugins' menu in WordPress.