Does your loved one love a particular sports team? Pick up a hat or a jersey you think they would look great in, or get yourself a matching one and cheer them on together!
Buy a pack of word magnets and leave little notes for your family on your fridge! This can be a fun way to create moments of affirmation throughout each other's busy days.
For the person who feels loved through Physical Touch, consider giving a back scratcher or massager that you can use to administer some relaxation sessions.
Acts of Service got you stumped? Designate a "Honey-Do" Bank in your home and ask your spouse to add suggestions. Every so often, choose a task from the bank and do it for him or her!