Place a heart-shaped doily inside one of the plastic cups, then very gently, slide the second cup inside the first. The doily may scrunch a little, depending on it's size, but it should still look fine.
The same applies for the food tubs; simply lay three hearts into the first tub, and slip the second inside. Remember that the lid and food are in the upper tub, so the food isn't touching the paper and if the bottom falls off, you will lose the doilies, not the food - all good.
You can use the tub to put some Valentine biscuits inside and give as a present and serve some pink lemonade in the cups for a mini-party at home. It's fast, simple, cheap, and personally, I think it looks rather pretty!