I need Help! How do I make this in less than 4 days?

Well when I cut the space for myself I wouldn't cut the box bottoms completely. I would leave them as flaps you can fold into the lower layer so that you can really attach them well so you don't risk accidently moving and breaking something. Covering the boxes in like wrapping paper should have a smoother look than just paint. Just make sure you don't forget the faux candles.