Page and Post Navigation

How can i add previous & next navigation in wordpress pages and posts.
I your Joomla demo you have it very nice at the bottom of this page https://demo.gavick.com/joomla25/photo/
I want exactly the same think.
I have managed to add somethink like this at the header, but it is working only for post pages.
You can see here http://5.9.65.247/~polizoidis/?cat=12&lang=el

Thanks

Hi,

You can decrease the category items number from your Reading settings, please change "Blog pages show at most" option, then the pagination should be visible.