I’m also just completing a 3D church for another competition I am involved in, with cardboard as a base, and several different types of paper to accent the look I’m going for. A good, wide open workspace is vital to a successful project, as are tools. I have two solid wood desks that I take over for more expansive projects.
I always try to keep my “zone” as organized as possible so I can find almost any tool I need at my fingertips. I keep my eyes open for any new gadgets to expand my collection, and frequently find little things to aid with future projects such as plastic, fabric, string, paper, cardboard, and a plethora of other fun mediums to make the job easier.
A clean workspace, great tools, and some good snacks :) are an integral part of a successful (and awesome!) project.