UPDATE: Before we go, its important to know that this tutorial is for previous templates. If you after installed the template see only HOME button on top menu than don't need to read this tutorial but just go to
Blogger Dashboard > Edit Post > Edit Pages > New Page and create easily new pages :)
Otherwise read this tutorial:
Menu Links that you see on your blog, actually are on your template code, is not hard to edit, just need to know when you should look on your template code, for this I will show simple tutorial with images.
Lets Go:
1. Log in --> Dashboard --> Design --> Edit HTML
2. Now you have to go to menu links which are on template code. Search [CTRL + F] About
(I choose About because most of my templates has this TEXT link on Menu, you can enter Log In or etc, enough that this word must be on Menu Links)
3. Now you should SEE something like here ( Check this IMAGE http://4.bp.blogspot.com/_iI6SgnnhWEM/S136WeV_w6I/AAAAAAAABHo/i7-UA_DZAWw/s1600-h/about.png )
4. Now to add Pages on those Menu Links read post below:
How to show Static Pages on your current Menu Bar > http://www.deluxetemplates.net/forums/topic/how-to-show-static-pages-on-your-current-menu-bar
5. If you want to delete, just delete only About text or all link
If you think, that you can write a better [easy to understand] tutorial, please contact me.