As much as commencement is a celebration of graduates' accomplishments, it's also a time to recognize the work of parents and extended family, mentors, and friends who made each graduate's journey possible. You can think of the academic regalia and pomp and circumstance as formal ways of expressing gratitude for what they've done for you.
While it's tempting to run off to say goodbye to everyone after you walk across the stage, be sure to introduce your parents to the people you care about most and encourage them to take lots of embarrassing photos with you. Because graduation is typically your parents' first opportunity to meet your professors and friends, try your best to use each introduction to paint a picture of what your experience was like. It's the least you can do to help them live vicariously through you.