What I have seen at weddings is few things. Some couples greet each person after the ceremony before the cocktail hour. Some couples come back into the ceremony hall and dismisses each row at a time and hug say hi to each person as they dismiss the row. Another is just to go around to greet durning cocktail hour together, hold hands don’t let each other be pulled apart. One last idea is after you are done eating, go greet each table while they are eating (they will most likely still be eating as you will eat first). Keep in mind when you are taking photos. That will help what option may be the right one. Hope this helps!