Right now, your child sees eating as an experiment. The more you allow her to explore, the more fun she'll have as she learns how to use her mouth and hands to eat. She'll enjoy how food feels between her fingers, in her mouth, on her face, and all over her body. She's also brimming with curiosity over what happens when she flings food on the floor or feeds it to the family pet.
Try to go with the flow and have fun watching her gleefully learn what food is all about. It may help to have a plastic, washable mat underneath her highchair to protect your floor or carpet (an old shower curtain works just fine). Outfit her with a large bib, one with a little pocket at the bottom to catch falling food if possible.
And for safety reasons, use unbreakable dishes, cups, and glasses. If she starts throwing utensils across the room, discourage the behavior with a firm reprimand. Give her smaller portions so she won't have too much material to play with. Otherwise, be prepared for lots of baths, laundry, and laughs.