Eva foam armor help

Hi im super new to cosplaying and am doing a group cosplay of deltarune characters with my friend my cosplay is going to be the roaring knight so I gotta make some black armor. Ive boughten a decent amount of Eva foam some 6mm some 4mm and am trying to get started however Im just getting lost and Im wondering if anyone has tips either this specific cosplay or just foam armor making in general. Im trying to take inspiration from ragegearprops cosplay of the roaring knight.