Score and fold along the dashed lines, opening it back up after each fold.
There are two #2 tabs; apply glue to the white area of one of the tabs and fold the other one over it.
Apply glue to the white area of the #2 tab that is now on top and fold the remaining tab down on top of it.
Note - this will be a three dimensional pop-up pyramid type piece. It is not supposed to be flat, so don't squish it down!