yehudah

Add a meta box to all posts, pages, custom post types to add the old url you want to redirect from (old url) to the new post. 
You can use redirection plugin here: <a href="https://wordpress.org/plugins/redirection/" rel="ugc">Redirection Plugin.</a> OR The other option is the website htaccess file.
This will help you create redirects while creating or updating your site posts or pages, so you don’t need to update the old and new links when you finish updating your website.
so you don’t need to remember:
<ul>
<li>The new posts or pages url</li>
<li>which post or page I all ready redirected ?</li>
<li>repeat 50% of the process again and so on ….</li>
</ul>

Redirect To WP

This will help you sync redirects while creating or updating your site posts or pages, This will sync to the redirection plugin or htaccess.

Silkalns

WP Chill

MantraBrain

Gangadhar Kashyap

Htaccess File Editor is a fast, safe and simple yet perfect to edit the WordPress site’s .htaccess file from admin panel. You can create a backup of your .htaccess file and can be restored from WordPress Dashboard. 
You can create a Backup from Htaccess –> Backup Menu and you can edit .htaccess file from Htaccess Menu. 
This plugin should be used only by experienced users!
<h3>Features</h3>
<ol>
<li>Edit .htaccess file easily</li>
<li>Create Backup of .htaccess file</li>
<li>Restore old .htaccess backup</li>
</ol>

Htaccess File Editor – Easily Edit, Backup, Restore .htaccess file


Does what it's supposed to do, no brainer!


Simple & useful

Simple editor htaccess file without using FTP client.

Redirect To WP vs Htaccess File Editor – Easily Edit, Backup, Restore .htaccess file