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.

Pavel

Using this plugin, you can create redirects for any post types or taxonomies.
How to use:
<ul>
<li>In the “Tools” menu, find the “Htaccess Redirect” menu item.</li>
<li>Select the post types and taxonomies for which you want to create redirects.</li>
<li>In the “New site domain” field, enter the URL of the site to which the redirect will be made.</li>
<li>Click the “Generate” button.</li>
<li>Insert the generated redirects at the beginning of the .htaccess file.</li>
</ul>

Redirects for Htaccess

Generates redirect code for .htaccess file

Redirect To WP vs Redirects for Htaccess