Layering the card is pretty straight forward and you can create a card as large as 6x6". I usually create square cards that are slightly smaller, around 5.75" x 5.75", so I can place them in the envelopes. However, with the supplies included, you can create a size that suits you. Each layer is 1/4" smaller than the previous layer.
I colored the door with light colors because I wanted the wreath to stand out. I have the colors I used somewhere on my desk so when I find them, I'll update this section. :D
Update: I found the Copic colors I used!
BG000, 53, B00
YG21, 25, 28, 67
R5, 12, 17, 29, 89
This is a limited quantity card kit so grab it while you can!