Moving my entire wordpress site

I have sold one of my WordPress sites, and I am trying to figure out the easiest way to transfer the entire site and all of it’s content to the new owner. I want this process to be completely seamless to the end users.

I attempted to copy all the WordPress directories and then just copy them to the new wordpress install (we’re trying to move to a test site before we transfer the URL), but it didn’t work.

Does anyone know how I can move the entire site. Pages, posts, comments, images, plug-ins, user database, etc… to a “clean” wordpress install?

Thanks in advance