No cosplay is complete without the Infinity Orb :p This thing is sick, real hit at any cosplay event, especially one that is Guardians themed. Along with your walkman and a good soundtrack you'll be set.
 
It comes printed in ABS in two pieces, I recommend painting them a black primer and paint, then brushing the silver onto the top surfaces! Gold interior and your set!
 
This file is freely available on thinigverse and credit goes to tonyyoungblood for this creation! absolutly sick good sir!