Step 1:
Prefold over these 4 lines,
then turn the paper.

Step 2:
First, valley-fold over the 2 lines at the bottom-right.
Then mountain-fold over the 2 diagonal lines in the
middle. And valley-fold over the 2 lines at the top-left.

Step 3:
Valley-fold over these 2 lines.

Step 4:
Unfold the folds of step 3

Step 5:
Valley-fold the tip at the bottom of the arrow upwards.

Step 6:
Push/press the edges flat/downwards.

Step 7:
Valley-fold the flap downwards.

Step 8:
Repeat steps 3 to 7 on the backside.

Step 9:
Bookfold one layer to the left.

Step 10:
Make an inside reverse fold over these 3 lines.

Step 11:
Bookfold the layer to the right again.

Step 12:
Repeat steps 10 and 11 on the left, see arrow.

Step 13:
Now the model looks like this.

Step 14:
Mountain-fold over the upper line and
valley-fold over the line below.

Step 15:
Valley-fold over the upper line and mountain-fold
over the line below.

Step 16:
Mountain-fold over this short line.

Step 17:
Pull the head upwards.

Step 18:
Make an inside reverse fold over these 3 lines
(=valley-fold over the line in the middle and
a mountain-fold over the 2 outer lines).

Step 19:
Push the head downwards again, see arrow.

Step 20:
Mountain-fold the model in half, except the head.

Step 21:
Hold the model the same as I do.
Press the head flat with your other hand, see arrow.

Step 22:
Now the head looks like this.

Step 23:
Valley-fold over this line,
do the same on the other side.

Step 24:
Pull the tip upwards by making an
inside reverse fold over these lines.
Do the same on the other leg.

Step 25:
Open the bottom of both feet, see arrow as example.

DONE! Looks like they are in a real bad mood...

This video also shows how to fold the Beast: