How to make an origami Hot Air Balloon

How to make an origami Hot Air Balloon
Designed by Jason Lin
Presented here by Jo Nakashima with permission of the creator

Diagrams and author website:
http://linhaiwen.wordpress.com/2012/0…

Difficulty level: Intermediate

My paper:
Tissue foil from origami-shop.com
http://www.origami-shop.com/fiche_art…
20cm x 20cm (changed to 40cm x 40cm at 15:15 to make clearer instructions)
I recommend 30cm x 30cm or larger sheet