Custom Mandalorian My custom armor where to begin?

So I've had a design like the one here:

some of the pain i used has faded so i should have repainted it

I'm really interested in making it from scratch and i heard sintra would make for the perfect armor. I'm just wondering about my helmet. SInce i have no Idea (pure honesty) in what i'm doing would it be better to try and buy armor or make it?

I've been getting tips from a fellow TDH member and from what he's told me. Sintra is easy to work with. You can also make the helmet out sintra as well but, if you don't want to make the dome part of the helmet out of sintra, you can use a helmet and work from there. It's my first time making armor and I will be making armor this week hope this helps

Here's the link to the armor templates, to get you started

http://www.thedentedhelmet.com/f20/all-boba-fett-armor-stencils-templates-23196/

Here's the helmet template and step by step guide to help you put the template together

http://www.thedentedhelmet.com/f23/all-boba-fett-helmet-stencils-templates-41929/

http://www.thedentedhelmet.com/f23/antmans-second-cardboard-scratch-build-24821/