Installation / Upgrading 
The Blog is quite simple to install or upgrade. The process is the same for each.
1Download the latest version of the Blog from the Members' Area. Be sure that you are running vBulletin 3.6.8 or newer!
2Unzip the file to your hard drive locally.
Warning:
Be sure to maintain the directory structure when you unzip the file!
3Upload the contents of the upload/ directory within the zip on top of your existing vBulletin directory. This is the directory with forumdisplay.php and many other files in it.
Note:
If you are upgrading, overwrite any files if prompted.
4Log into your vBulletin forum's control panel. Go to Plugins & Products > Manage Products > Add/Import Product
5

In the Import the XML file from your server field, enter: ./includes/xml/product-vbblog.xml

Change Allow Overwrite to yes.
6Click Import.
If all went well, you should see a message saying your install or upgrade was successful! That’s it!
Note:
There are more detailed instructions on how to unzip and upload files in the Installing vBulletin section. These may be helpful.

Note that there is no config.php configuration file in the Blog. You do not need to perform this step.
Shai 28th Oct 2008, 08:45am
If you renamed your admincp/ directory when installing vBulletin, then you should manually copy the files under upload/admincp/ directory of the blog distribution, into your renamed-admincp/ directory.