Hi. I work with Wordpress all the time so this isn't a problem for me. Instead of manually adding code I would edit the template in PHP, which would add the next and back buttons on all the pages required, without you having to worry about it any more.
Although I am new to freelancer.com, in my portfolio you can see some of the work I've done for other clients. I am ready to start working on your wordpress site rightaway.
Robert van Engelen
Driewieler Digital