You do the file edits to the files that you downloaded from vb.com. You know, the ones that you uploaded to your website under the "forums" folder before you installed the software. Just open them with a text editor (I use metapad, but notepad works good too) and use the "find" feature to locate the code. Once you've made all the changes to the file, save and upload it.
Also,
read this for more help on how to apply hacks.