Weddings often are costly affairs, but with enough advance planning and a little homegrown ingenuity, you can make things instead of shelling out for them.

Wedding magazines and Web sites help, too.

"There's nothing you can't craft for your wedding," said Darcy Miller, editorial director of Martha Stewart Weddings magazine. Among other items, she mentions gifts, decorations, flowers and the cake.

Ah, the cake.

The Knot Inc., which runs two wedding-related Web sites, surveyed the spending habits of 18,000 couples who got married last year, and found that on average couples spent more than $500 on a professionally decorated cake. There are ways to limit that cost, Miller and other experts say.

For starters, craft your own cake topper, and end up as well with a keepsake.

A recent Martha Stewart Weddings favorite, for example, was clustering colorful, craft-store butterflies along one side of a fondant cake, Miller says. Another: Top the cake with a tea cup, either from grandmother's inherited china or from your own, registered china.

Another lively topper comes from Real Simple Weddings, an annual guide published by Real Simple magazine: Deputy Editor Jaimee Zanzinger suggests placing tiny images of the bride and groom in elegant frames on top of the cake. She's also seen small cornhusk dolls adorn a cake's top, and notes that many of these craftsy items can be commissioned.

Teri Bellman Garvin, 38, of Golden, Colo., ordered a simple fondant cake from a baker for her own April wedding, then personalized it herself with a mountain-biking theme. Instead of paying the baker nearly $100 for chocolate-covered strawberries that were supposed to mimic boulders, she and her husband, John Garvin, substituted chocolate truffles from their local Whole Foods Market.

Garvin says the design represented the couple's passion for cycling on trails near their home and the force with which they fell in love. The cake had two trails running up either side and meeting at the top. It was crowned with two, iron-crafted figurines -- hair-tousled caricatures flying off their bikes -- that Garvin purchased from an online shop.

"That's how life is," Garvin says, explaining her cake. "You're fooling around on your own path and then crash. You meet someone who changes your life. Luckily, we weren't on our bikes falling head over heels when we met."

Both Miller and Zanzinger note that wedding cakes are getting smaller: Brides are straying from the traditional three tiers and supplementing cake with other desserts.

Cakes also are getting more colorful as brides shun the traditional white or ecru in favor of something more daring. Sugared flowers, which pop up the cost of a cake, are losing favor. And cupcakes or mini-cakes -- one per seated table -- are gaining in popularity.

"Couples today are wanting everything personalized in their wedding, especially something like the wedding cake," said Miller.