Your placecards and favors are one of the details at your wedding where you can get creative. If you're a pilot, an air traffic controller or even just an airplane aficionado you could do something similar to the picture on the left.
It's a good idea to arrange placecards alphabetically with the table number on the back, also like the picture on the left. This will help you to avoid everyone circling the tables trying to find their placecards, and it will prevent someone getting to the table 6 first and switching your know-it-all aunt Sophie to a different table.
When it comes to favors keep it simple and elegant. You don't want your guests to feel like they just got something out of a Cracker Jack box, but at the same time you can't afford to buy everyone a pair of diamond earrings. (If you're reading this Oprah, it doesn't apply to you.)