Your bride and groom sit at a table at the top of the screen. Guests enter and it is your job to seat them, preferably next to or not nearby the people they specify. If you do, you get bonus points. Seat them next to someone they don't like and they will grumble and you'll get fewer points. Then, you take their gift to the bride and groom, then serve them an appetizer, an entrée and cake, in that order. Once they are done, they mosey to the dance floor. Sounds simple? Not really. Sometimes you may have to wait on the cook to finish prepping the food. Sometimes the A/V has issues and the music dies, forcing Quinn to go fix the problem. When the bridesmaids bust out into a reception-ruining fight, Quinn has to break it up. She also has to fend off bugs and put out kitchen fires. It's crazy I tell you! Then there are the troublesome guests, like the crying old aunt and the drunkard uncle, both of whom make other guests miserable. Quinn has to quiet them down or the other guests get angry.
Basically, you have a point goal and you can only make this goal if you don't screw up too much. Keeping the wedding guests happy leads to bonus points and you'll reach your goal. Not realizing the music is off and the people on the dance floor are mad lowers your score. If you are super good, you can go for the expert goal, but like I said, this game is tough and personally, I didn't achieve expert all that often. If you don't make your goal, you simply replay the level.