Today I was working on my blog and started styling comments.php in my WordPress theme – this wasn’t too difficult but still took me a couple hours to sift through PHP/Wordpress jargon to find the HTML/CSS code I was looking for. Before long I wanted to style the actual comments posted by users. To my dismay I learned the code for user comments is not in the comments.php theme file but rather in the comments-template.php file in the WordPress wp-includes/ folder. Bummer.
Customizing the WordPress wp-includes/comments-template.php file is extremely complicated, even to a veteran PHP programmer, and after messing with it for 2 hours I started searching Google for a guide. I found out through various guides that the wp_list_comments() function called in comments.php can take a callback function as a parameter that will use a custom comment function as opposed to the WordPress default. By using the callback parameter to point to your own function, you can really take control of the WordPress comments style and structure.
I found a great guide that will take you step by step through creating your own comment function for the wp_list_comments() function to callback.
Also, for background information on wp_list_comments() and a full list of it’s parameters: