Started out like everybody with foam, tracing the templates.
I made my templates out of files i got from destinystlgenerator.com.
Cleaned them up in meshmixer, andunfolded them in pepakura designer.
Construction of the chest base.
Making of the chest plate that goes on top
Put some more detail on it out of 2mm craft foam, the 'belts' on the shoulder are made from 5mm high density EVA foam textured with a heat gun and a ball of aluminium foil.