1) Romantic things to do to his phone. Replace his phone's background image with a cute picture of yourself, for example, blowing a kiss.
2) Romantic things to do to her lunch bag. Use a toothpick to write a special note on a banana peel. After a few hours, the bruised skin will reveal your hidden message.
3) Romantic things to do in the car. Collect meaningful odds and ends like movie tickets and vacation souvenirs, and leave them in the car's cup holder.
4) Romantic things to do in the kitchen. Drop candy hearts in a sugar bowl, a go-to coffee mug, or any other knickknack.
5) Romantic things to do in the bathroom. Rub soap onto your fingertip and write on a mirror. Lightly trace over the letters with a tissue to ensure that they aren't easily visible. When the bathroom steams up, your words will appear.
6) Romantic things to do in the living room. Spell your sentiments with Scrabble tiles.