After you installed an SSL certificate for your domain, you may want to re-direct your visitors from http:// to https://. This will help your webpage load securely. Now, google search ranking also supports https://, this will also help your SEO.

You can modify your .htaccess file and add the following code to the beginning of your .htaccess file:

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{HTTPS} !=on
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
</IfModule>

Your .htaccess file needs to be in the root folder of your website to make it works.