Hi mate, thank you for your question. Please follow these steps:
Step 1: copy/ paste the following code to your functions.php file
https://snippi.com/s/do35pka
Step 2:
creating a php file for your custom template. This file will be used for your custom template. You can name this file anything you want. In this example we will name it customsingle.php. Don’t worry about the content of this file. You can copy the codes from your normal single.php of your template. Put this new file on your theme directory.
Step 3:
add a special comment on your new file
You can edit anything on your new file, such as removing the sidebar section or anything. But, in order to get your file work you need to add the following comment right after the php opening tag. Here is the code.
<?php
/**
* Template Name: [Custom single template name]
*
* Template Description…
**/
?>