Well... before I ask... what is your experience in web designing?
For starters... you should know html5/css3 (obviously) plus you should know some jQuery, PHP, and some MySQL for some of the backend material (except you use jQuery to do some of the things like making sliders, menus, etc.).... That being said...
Do you have a site that you are trying to "copy" in a way? If so, use your web inspector tools (firebug is a good one). That will help you design the page (which is what your article is titled) but to build the functions... that'll involve some thinking but lucky for you, we are here to help you with the backend materials (such as datamanipulation and storing as an example)!
Personally, I think its best for function first than design... but hey, it's not the same for everyone.
If you have any more questions, ask away!