Again, décor depends on the theme, so figuring that out should be first and foremost on your to-do list. Décor should match the theme as well as your bride, so if she wouldn't love it, it's safe to say you should skip it.
Do you need a guest list?
Okay, so you're not planning a Saturday night at the 40/40 Club, but you still need to know who to expect. Start out by stealing a copy of the master wedding guest list, once it's finalized. You'll only want to invite the ladies you plan to have at the wedding. Yep, that means you'll need to invite everyone from Great Grandma Bee and the groom’s third cousin Susie to your friend’s pesky coworker. A tip? Start a Google Doc to keep track of whose RSVP'd and who you're still waiting to hear from. On the day of the shower, print it out and keep a few pens nearby. You'll need to keep track of who gifted what, so the bride can write her thank-yous.
Do we have to be polite?
The short answer is yes, because you're spending the afternoon surrounded by faces you'll likely see again (at the wedding), so you don't want to leave a sour taste in anyone's mouth. The long answer is that though we're living in a modern age, weddings are still incredibly traditional, so people expect a certain type of behavior. A good way to differentiate? Be a lady at the bridal shower and a freak at the bachelorette. Okay, fine, not exactly what Ludacris sang, but still, it's useful.
You don't have to plan tons of games (especially if your bride isn't the gamey type) but a few tongue-in-cheek quizzes to pass the time are usually appreciated (and fun!). The best times to play? Before the main meal is served and before dessert. It helps break up the party and won't distract guests from the main event — the gifts!