You say "Category" ?? but if you just need an extra menu item after random then.....
Create a copy of the theme, and then edit header.php and put it in:
app ==> themes ==> yourtheme ==> overrides
Find:
Code:
<?php if(CHV\getSetting('website_random')) { ?>
<li id="top-bar-random" data-nav="random" class="top-btn-el phone-hide">
<a href="<?php echo G\get_base_url("?random"); ?>"><span class="top-btn-text"><span class="icon icon-shuffle"></span><span class="btn-text phone-hide phablet-hide"><?php _se('Random'); ?></span></span></a>
</li>
<?php } ?>
Add after:
Code:
<?php { ?>
<li class="top-btn-el">
<a href="http://www.myblog.com"><span class="top-btn-text"><span class="icon icon-home"></span><span class="btn-text phone-hide phablet-hide"><?php _se('Blog'); ?></span></span></a>
</li>
<?php } ?>
Think that should work.
You might need to change the icon to something you like. In that code it's "icon-home", not sure if there is a icon-blog you'd need to check. You'll also need to amend the url for your blog site.
You also might need to make your logo smaller as it could "crash" into the extra button
๐