Page to external link how-to

I am trying to get my Forums page to link to my phpBB forums (eg forums.mysite.com) and I haven’t found a clear answer as to how to edit where the page link directs you to. I tried looking through the data base to edit the link to send it to another URL but couldn’t find the entry. I also found a plugin called redirectify but it didn’t work seamlessly for me. Where would I go about changing the URL that my forum page links to? Thanks