Though it is important to like the design and color of your swimsuit, it's more important how it looks on your frame. Some suits, while they may be the right size, don't look as good on your body because you have the wrong style.
The best styles for petites are triangle, bandeau and push-up. Triangle bikinis have adjustable tops that help enhance a smaller bust, and the bottoms are cut perfectly to show off your small legs. Bandeau styles are also great for petite girls because the ruching creates perfect curves. And of course, push-up bikinis create cleavage, something many smaller females want but don't have.
Check out Hollister's Orange County in Dark Orange (top $34.50, bottom $24.50)--the floral design also helps fill you out. Hollister also has three great push-up styles, and check out American Eagle Outfitters for cute triangle bikinis.
So this year, don't just wish for the perfect swimsuit--get the perfect swimsuit!