After attempting this myself I realise that the instructions in the presentation were a little vague.
If you want to try the square, start with an A4 piece of paper.
Once you have followed the instructions for the first fold, which will give you a square piece of paper, all other folds are up to you.
Try to form triangles across the page then unfold and start again going a different direction.
How many triangles can you make folding the paper in half each time. I managed 5 but you have to make your folds accurate.
Now unfold the piece of paper and look at the pattern.
Could you fold part of the paper to create even smaller triangles.
Experiment with it then use a black marker and a ruler to draw on the creases. You could colour in the different shapes to make your own pattern.
Another option is to use two different coloured pieces of paper and cut out all the shapes at the end and create for own pattern. Possibilities are endless.
Good luck - What can you create?