What are some waterproof materials that meet my criteria for folding origami stars and cranes eggs? One of my future projects involve folding A LOT of origami stars and crane eggs and turn it into a curtain. However, I want to insure that my hard (and very tedious) work do not go to waste by making it waterproof.
Here are images of both the origami star and cranes egg:

To fold these you start with a thin piece of paper about 5/16 - 1/2 inch wide and about 8-11 inch long.
Criteria (in order of importance):

Waterproof (enough to withstand some splashes of rain if the window is ever left open accidentally)
&quot;pliable&quot; enough to fold but firm/thick enough to keep the shape of the origami
Come in long strips of about 5/16 - 1/2 inch wide
Able to come in multiple colors
Relatively inexpensive

Some materials I've tried:

Waxed paper(used in the kitchen) - These fit the waterproof and inexpensive criteria but needs to be manually trimmed to size. They also don't have enough weight to really hope the shape of the origami too well.
Satin ribbon(used in gift wrapping) - These were beautiful and water proof but were too cloth-like and unable to hold the shape of the origami.
Laminated strips of paper - These were annoying to prep and too rigid and thick to fold into the origami.

I'm willing to compromise on one or two criteria if it at least greatly meets three of my criteria. Optimally hoping theres some magical material that perfectly meets my needs though.
You could try using palm fronds, which can be woven to make beautiful stars and patterns:





For more details about the craft of palm weaving, see this question and the links given in its answer (disclaimer: answer posted by me).

They're obviously waterproof, since they come from plants which are naturally found in wet conditions. They come in long strips, which are (perhaps surprisingly) pliable enough to be folded into intricate shapes but also strong and tough enough to stay in shape. They should be inexpensive, at least if you're living in the right region (e.g. somewhere there's a strong Catholic community with a tradition of palm-weaving). The only criterion they don't meet is being able to come in multiple colours, but it might be possible to paint the palm fronds before folding them, if you can find a paint that works well on organic material like this.