There's not a whole lot of information out there about WAP development. Don't sweat it, we've all been there. Specifying the hierarchies of your pages. Linking your pages. WML tends to be easy to learn, simply because there's not a whole lot to the language.
Mobile phones have slower operating speeds than PCs.
Thus, pages that display on mobile phones need to have quick download times. WML allows for quicker download times by giving up some functionality. What this means is that most WAP applications will actually be made up of a number of pages.