This beautiful Wind Mill paper craft is an easy to build model from Phan Khai.
A windmill is a mill that converts the energy of wind into rotational energy by means of vanes called sails or blades. Centuries ago, windmills usually were used to mill grain, pump water, or both.
I think the source is from kirigami club.
Anyway it comes with instruction guide in the form of a video which should help you a lot.