This is one of my favourite DIY's to give to a loved one.
You get some popsicle sticks and write date ideas on it for the future. colour code the popsicle sticks according to the price range of the date. Or instead of dates you can write a cute message or IOUs on each stick.
Picture from here!
Image is from here!
I hope my ideas have helped you! If you're in a last minute rush theres always the cliché of chocolate and roses!