Centerpieces can be so many things. Think of what this word will be the focal point of your event. It is nice to incorporate things that say something about you. For example, if you love to read books, stack them and use them as pedestals.  if you like antiques, collect your containers from flea markets and antique stores and fill them with flowers. Add table numbers, table runners and lanterns or candles, all will bring your attention  to the center of your table. Feel free to make your tables different from each other, as long as you have something that ties them all together some as color or a certain type of flower.