I cut up a box I had on hand and ducttaped it together.
Cut out a hole for the head and arms make sure the hole for the head is smaller than your lego head or else it won't sit well. I later added foam pieces to keep the head I place but forgot to take pictures.
I used my old protein bucket for the head and just cut the bottom off. I painted the whole thing with burgundy, white, and gold acrylic paint and used a paint pen for the details.
I made some lego hands that didn't turn out the greatest but I cut out the shape on cardboard and used foam to separate the two sides and paper mached them leaving a hole in the middle for my son's hands. I was in a rush the night before halloween and didn't bother to try them on him so his hands didn't fit great haha. Oh well.
I found a burgundy shirt and pants at Walmart and called it a day!
Oh and I found the light on his chest at lowes, I hot glued it to the front and we used it as a flash light while trick or treating! :)