Quick newbie question!

Hi all! I use the water 1.1 theme
http://themes.wordpress.net/columns/2-columns/715/water-10/

I set my blog so only one post is displayed per page.
The next page option is located on the bottom of each page
beneath the post. The font for “next page” is kind of small and readers may not see it if the post is too long. How do I make the font for it bigger and add a “next page” to the top of the past as well?

Thanks in advance!