Howdy, and welcome!
I think that question could be better answered with just a tad more information. Do you have any previous experience that you think might apply to this project? Are there any materials you might be more comfortable with or have better access to? And, of course, have you breezed through the stickies already? Because they do a pretty good job of familiarizing you with the most common practices around here.
There are basically two approaches. The pepakura -> Fiberglass -> Bondo method, or EVA foam -> Flexible sealant method. I would say It is important to look into these thoroughly for yourself and decide which you feel that you will be more likely to follow through on.