How to place an item on top of another item

STEPS:
1. Drag the item by pressing the left button of the mouse and place it on top.
2. Then press the right button of the mouse and gradually release the left button.
This will make the item stuck in place.
3. Save it by clicking the check button on the screen (the green button on the lower right portion of the screen, on top of the "Award" button)
4. You will notice that the item is nowhere to be found (because its invisible)
5. Save the game and re start it.
6. You will now see the item on top of where you placed it.