Use a variety of color pens to write a list of reasons why you love each other on separate blank pages. Reasons can include personality traits, shared memories, warm gestures from the other person, etc. You can also print out pictures or ticket stubs or other physical things that represent a particular reason and paste them in. Sign your name and date at the bottom of each page. Go through the scrapbook from time to time and add new pages to see the relationship grow. Give it to each other as a gift to reflect on your love for each other.