It’s folded from 6 octagons of different sizes that you cut out of squares after some pre-creasing. Follow the link below for the Crease Pattern.

No cutting or gluing required to make the units but you may want to add a dab of glue between them for more stability (though I didn’t). Great design to make and decorate your home or office for the Holiday Season!

Name:	Bialbero di Natale – Double Christmas Tree
Designer:	Francesco Guarnieri
Units:	6
Paper ratio:	octagons (cut from square sheets)
Assembled with:	no glue
Paper size:	21, 19, 17, 15, 13, 11 cm squares
Model size:	~ 13 cm
Paper:	Sugar paper
Diagram:

Here is a quick guide on how to collapse units after pre-creasing.
[See image gallery at goorigami.com]

Origami Christmas Tree