Show Blog Directory on all site

I have the blog directory working on the main site however I need this page to be on all the sites on the network so users can switch between any site on the network regardless of what site they on.

As it stands they can only do this from the main site which some might not even know about.

We need a user who lands on any sites on the network to be able to see the blog directory on that site to visit other sites on the network.

I may have missed something or set it up wrong so if can advise how we can achieve this that would be great.

Thanks,

Frank