How to create inner post pagination?

[eluser]Unknown[/eluser]
Hey there,

I just bought a site that uses codeigniter as it's framework and have no experience in it whatsoever. I'm basically just looking for a bit of help to improve my new site [link]. On each post I would like to create pagination to the post before it and the post after it.

How could I go about doing this?

Thanks in advance!