So you are tired of losing visitors due to 404 errors on your website? While you should do your best to fix those, you can use plugins such as WP 404 Auto Redirect to Similar Post to redirect visitors to similar posts. This plugin automatically detects 404 errors and searches for a similar post to display based on title, taxonomy and post type.
This plugin also has a fallback option, so in case no match is found, you can send visitors to your homepage or a custom URL. It supports 301 and 302 redirects. Want to exclude certain posts, terms, and post types? No problem. This plugin can also log redirects.