Two layered perspex heart with a light source inside it, to signify your burning love.
Step 1: The pattern
First, you need a pattern for the heart. Draw half a heart on the left half of a sheet of paper, then darken it with a soft pencil.
Fold and rub along the line so that the carbon from the pencil lead transfers to the other side. This gives you a symmetrical heart.
Darken the faint outline, too, so that it is easily visible. Make any corrections as needed.
Now you have the paper pattern for the heart.