I realised that I had not added the struts to the inside of the box to attach the decorations to, so die cut two from 300gsm card. It is important that they are folded into a zigzag shape and that they both fold the same way when added to the inside. It is also important that they be level, so I chose to glue them level with the top inside edge using double sided tape.
To decorate, I cut the Marianne Ice Crystals Arc. the Sue Wilson Christmas Angel from 2015 and one of the Sue Wilson Star Spray dies out of Sheena's stamping card. The Ice Crystal Arc was 'coloured' with a clear Spectrum Noir Sparkle pen and once dry twinkles wonderfully (not that it shows up in the photo). The angel was coloured with Pearl Lustre Metallic Gilding Polish and the Star Spray with Silver Dream metallic Gilding Polish.
To start with, I glued the Crystal Arc directly onto the inside back of the box.
I then attached the angel to the front of the cross strut nearest the back of the box.
Finally I added the Star Spray to the front of the other cross strut. Each time I ensured that the box would fold flat and would still fit into a 6"x6" envelope.