In my understanding of human courting rituals, which I admit is limited, creativity and thought are highly appreciated when it comes to gifts. I would suggest making something, as that can represent a more personal affection and requires time, energy, and focus on the individual, all of which the intended will recognize. Popular options in my database include: writing a poem, drawing a picture, making a scrapbook of your time together, designing a piece of jewelry out of materials significant to the couple, composing a song, and cooking dinner.