Money Heart Bookmark

Start with a crisp dollar bill with the green-side facing up.
Fold and unfold into quarters lengthwise.

Fold up the bottom-left corner to get a diagonal crease.
Unfold.

Fold down the top-left corner to get another diagonal crease.
Unfold. You should get an X-shaped crease.
Turn the dollar bill over.

Fold in the left-edge of the dollar bill.
Make the fold so it intersects the X-crease made above.
Unfold and then turn the dollar bill over again.

Pinch the dollar bill near the vertical crease.
At the same time, fold the left edge of the dollar bill towards the right.

In progress. Once the the fold is complete, you will have a triangular flap on the left side of the model. This form is called a waterbomb base .

Fold the tip of the waterbomb base (the triangle) to the base of the triangle.

Unfold. This crease will be useful later.

Lift up one of the flaps of the waterbomb base.

Fold up the bottom 1/4 of the dollar bill.
Use the crease made in step 1 as a guide.
Make sure that the fold goes under the waterbomb base; you will need to lift the layer on the left so you can tuck the fold under.

Pull down two flaps from the waterbomb base.

Repeat step 8 on the top of the bill: fold down the top-edge of the dollar bill. Remember to lift the waterbomb base so the fold goes under.

Fold back up one of the waterbomb flaps.
This should give you something that looks like an $ arrow

Fold the top layer of the waterbomb towards the left.
Use the crease made in step 6 as a guide.

In progress.

Make valley folds so the paper lies flat.

In progress.

Fold back (mountain fold) the corners of the dollar bill as shown. You will get a heart shape.

Swivel the right side of the model to the left.

Rotate and the Money Heart Bookmark is complete!
Below is an image of how the Money Heart Bookmark would look like had you started with the black-side of the bill facing up.