So these are the instructions for an origami water cup.
For the origami water cup, I’m going to grab one sheet of paper.
The first step is going to be with the white side up, we are going to fold a diagonal fold, so take the bottom point and fold it all the way up to the top point. Make sure that it is nice and precise so that there is no white showing. Get it as exactly as you can and hold it in place with one finger and use your other hand to side the finger down.
Then use your thumb to hold your place for you and as you go out to the corner on one side and also on the other side. Just like that. That's a good diagonal fold.
Next we are going to do a kite fold. We are going to fold this edge right here and we are going to fold that down all the way to the bottom.
Now the only thing we actually need here is to get it to line up and then find this point right here. You can fold it all the way down across if you like, but the only thing that we actually need is that spot right there. So go ahead fold that and unfold it.
Now we are going to take the bottom left hand corner, and we are going to fold it and put it exactly on that spot that was I was pointing to. That spot where that crease hits this side edge of the paper right there.
Fold that over and now we are going to take this corner and fold it over to this spot right here. Like that. That gives us the front and now there are two sheets of paper right here, I am just going to fold one sheet down on the front. Flip it over and then fold the other sheet down on the back.
Then open it up and that is a traditional origami water cup, and yes it does hold water.