There is a making-of/tutorial of my princess Zelda Ocarina of Time armor
It was the very first one I made. I had absolutely no experience in armor-making, so I made it out of paper mache because it is very lightweight, easy to paint on and easier to "mold" than plastic or craft foam (well, in my opinion at least). It is also cheaper and sturdier. Mine cost me around 20$, and that represents the cost of the gesso only. Everything else was found around me house
If you want to make an armor yourself, please use this for advice only and read a LOT of different tutorials. That way you will be able to find the most suitable method for you
If you have any questions, feel free to ask them and I'll to my best to give you a good answer!