Unless you're a magical princess with a model's physique-and if you are, congrats!-you will likely need wedding gown alterations. Fear not; two local experts explain everything you need to know about achieving a perfect fit for the big day.

Unless you're a magical princess with a model's physique-and if you are, congrats!-you will likely need wedding gown alterations. Fear not; two local experts explain everything you need to know about achieving a perfect fit for the big day.

Begin at the beginning

"The alterations process for a wedding gown starts the minute you walk into the [bridal] store," says Joyce Eubanks of Alterations on Lane. She compares wedding dress shopping to building a house: Both need a strong foundation. With gowns, that means knowing what styles look best on you.

"If you start with the right [dress]," Eubanks explains, "the alterations are gonna go a lot smoother."

And if you're between dress sizes, always go up.

"It's always better to have the dress slightly bigger, because it's easier to take in than to let anything out," says Laura Stith of Creux Poche. Matching fabric from a store to your gown is nearly impossible, she explains, and Eubanks adds that manufacturers often charge hefty sums to buy extra yardage of their fabric.

Timing is everything

Your alterations timeline depends largely on how much work your dress needs. Eubanks suggests researching and interviewing seamstresses a few months before your wedding. Many bridal shops can recommend a house or contracted alterations specialist, but Eubanks says recommendations from friends and family can go a long way, too.

During your research, ask about base costs for alterations you know you'll need, like hems and bustles, and be sure to tell the seamstress the style and fabric of your gown.

If your wedding is in peak season, you might make your initial appointment eight or more weeks before the big day; it all depends on your seamstress' schedule. Plan to pick up the final result a week or two before the wedding, says Stith, so you have time to get it professionally steamed.

Both Stith and Eubanks caution against picking up the dress too early; if your weight changes, you might have to pay extra for a last-minute fix.

Who (and what) to bring

"Sometimes [brides bring] the maid of honor … because she's usually the person who traditionally bustles the dress, so I can show them how to do that," says Stith. And Eubanks adds family members or friends who know how to sew can be helpful, too.

Eubanks and Stith agree that one of the most important things you should bring is the shoes you'll wear, to ensure a proper hem measurement.

"Any supportive undergarments are especially important so you can make sure … that none of it shows, that it fits right and you don't have any bulges," says Stith. "Also if the dress needs any kind of crinoline or underslip, you want to bring that too, to make sure it hangs right and that the hem is the right length."

For the 'maids

Bridesmaid dresses often only need to be hemmed. To avoid sticker shock that might accompany more drastic alterations, Eubanks suggests having your hardest-to-fit bridesmaid try on the options before you make a decision.

Bridesmaids can plan for turnaround in two or three weeks, depending on the season, but that doesn't mean they can leave alterations to the last minute. They should contact seamstresses a month or two in advance to be sure someone can fit them in.