Demi Moore has revealed how she and husband Ashton Kutcher keep the romance alive in their marriage.

“I’m an old-school romantic, so I get giddy when Ashton shows me another way of saying “I love you” – any little thought or gesture that’s playful or sweet,” she tells US Glamour magazine.

The 48-year-old actress has just directed Charlotte, a short film about a woman touched by breast cancer.

“We leave Post-it notes for each other; some have been sticking up for five or six years. For me, it’s the small things. The first day of filming Charlotte, Ashton sent this bouquet of soft blue flowers with a card that said, “I believe in you.”

“I put them in this little room that I parked myself in while we were shooting in the rest of the house,” she gushes, “and that was the room that we shot my movie’s final scene in.”

The couple, whose sixth marriage anniversary is coming up this month, have been working together on their most important project yet: fighting sex trafficking. They launched a campaign called “Real Men Don’t Buy Girls” as part of their Demi and Ashton Foundation. Watch some of their hilarious videos starring Justin Timberlake and Ashton Kutcher himself (look out for the surprise appearance from Eva Longoria!)

How do you keep the romance alive in your relationship?