Help! I need to add a link to my navigation

Hi,

We had a company redesign our website back in 2011. I setup a blog in WordPress and would like to add it to my main top level navigation of my site. I see that they used CKeditor within our CMS. What I need to do should be fairly simple most of you I'm sure...I'm just getting familiar with this so I'm not able to figure it out

I want to create page on my navigation called BLOG. When clicked I want it to go to the specific directory I have the Wordpress blog hosted on www.focus-usa-1.com/blog...however, I don't know how to update my index.php or navigation.php script in order to allow for this.

Please let me know what I am doing wrong.

Thanks
John Fleming