Here are a few simple steps to keep your self-hosted WordPress installation up-to-date:
Backup your database regularly. There are plugins to help, and many web hosts offer tools too.
Backup your theme and plugins.
Schedule your backups based on how frequently you update your site, change the theme and plugin files, and how many comments you receive.
Store your backups in a location other than the webserver.
Delete unused and inactive themes and plugins.
Make a special backup before you update WordPress. To receive notice of updates beyond the announcement in the dashboard, sign up for the email announcement list or follow @WordPress on twitter.
This post follows up on the tech tip I recorded for Episode 271 of the Just the Books podcast. This continues the series about websites and how they’re made, looking specifically at WordPress. This series is not intended to deeply explore the topic, the primary goal is to build a foundation for understanding how websites are put together, the tools that can be used, and how innovation is changing and advancing this topic.