2. Fold the right edge down to meet the bottom edge,
folding at a 45 degree angle that goes through the
lower left corner.

3. Fold the right edge over, along a fold line parallel to it,
so that the right edge touches the lefthand part of the
top edge, which is vertical because of the first fold.

4. Tape the right edge to the lefthand part of the top edge.
Tape the remaining part of the top edge to itself.

5. Now open up those folds, and fold the right edge
against the righthand part of the bottom edge, and tape it.

6. Finally tape the remaining portion of the bottom edge
together.

Note: Dollar bills don't tape so easily,
and they resist flexing. Try a thin sheet of paper
of the same shape. Once you have everything taped,
the paper should flex into an appropriate polyhedron.
The one that I have suggested is just one of many.