Coffee tables are those pieces that are necessary and have a lot of great potential but are often ignored when it comes to decorating. If you think about it, coffee tables are actually in the center of your room, so they need have a little style! Don't let something that's sitting smack-dab in the center of a space go naked! Dress it up!
When dressing up your coffee table, always consider function, but don't let that limit you! Sometimes you need things that just look pretty, even if they don't always have a use. A coffee table is a great spot for those sort of things.
Since the coffee table is a small space and, even though you want it to look finished, you don't want it to look cluttered, you'll probably want to use a tray to group the objects you place on it. A random object floating on a coffee table doesn't do much for the look--you're trying to create a vignette that will draw positive attention, not confuse.
Trays come in all shapes and sizes so, no matter what shape your coffee table is, I'm sure there's a tray out there for you that will fit! Don't use something with a really low lip, like a platter. Go with something that really visually contains the items and has a large enough lip to give this effect. Also, select one that's large enough to hold a few different items. A tiny tray that will fit one little vase is useless in this scenario. Once you've figured out size, determine if you want it to blend in or stand out. Do you want it to create a contrast or blend?
Once you've selected your tray, figure out what you need to be in the tray? Do you have a "coffee table book" that you'd like to incorporate? Do you always keeps fresh flowers on the coffee table? Coasters? Magazines? Candles? What is it that needs to go on it? Once you've determined that, consider height. If you don't have items that vary in height, play around with stacking to create different levels visually. Also consider color. The coffee table is a great place to add a pop of color without much commitment. A small figurine, a flower arrangement, or a pretty bowl can all add this. Finally, consider shape & texture. While three vases at varied heights can be fine, it makes the arrangement more interesting to vary texture and shape. The little pieces that are sitting on your coffee table can easily be considered art!
Overall, the items you place on your coffee table are link the jewelry to an outfit. They spice it up, make it a little more interesting, and add a finished feel to the overall look. Don't let your coffee table go naked!