You're on a quest for the dress of your dreams. You've found it and it takes your breath away…but it doesn't quite fit. The salesperson assures you it WILL fit when you head down the aisle. How can you be sure it's not just a sales pitch?

Following the suggestions below can ensure that on your special day, everything looks -and fits- just as it should.

Know your size. Bridal sizing differs from sizing for street clothes. Often, it's two sizes above your regular size. If you're interested in a particular designer, investigate their sizing guide so you can know what to ask for at the boutique. You want the size that comfortably fits the largest part of your body and is as near to yours as possible: something too big will almost need rebuilding if you purchase the sample (not cheap), and you may not like the fit when ordered. Similarly, it's difficult (and costly) to let out a dress more than one or two sizes, especially if the fabric offers little seam allowance (such as silk, satin, or velvet) without the original seam line showing.

Leave the clamps at Home Depot. Every wedding show brings out those big white clamps to give you the perfect silhouette in the gown. However, sometimes the image in the mirror isn't what you'll get once it's altered. Instead, ask for someone in alterations to come pin the dress, if possible, so you can get a feel for what the actual modifications to the dress will look like.

Ask about the fine print. Some bridal salons advertise "free alterations". Unfortunately, that often means the minimum- taking up hems, shortening straps, repairing loose beadwork, etc. That doesn't necessarily include taking in or letting out a dress several sizes, altering the waistline, or adding additional beadwork or sleeves. If extensive alterations aren't in their included offerings, you may be best served by having your work done by a tailor or modiste. Also, hire a professional or work with a friend or family member with extensive experience with bridal/formal wear: your wedding dress shouldn't be someone's learning curve.

Make an appointment. If the boutique offers alterations appointments, I strongly suggest you make one. Find a slot that allows for a full hour; don't try to squeeze a fitting into an already busy day or your lunch break. Ask the shop to recommend a good time to come in. Alert, kind seamstresses and brides are happy seamstresses and brides! Make an evening appointment on a weekday (avoid Saturdays for fittings if at all possible). You want their full concentration on your dress.

Bring your foundation garments and shoes to ALL of your fittings. Yes, this is absolutely necessary. They should also fit correctly. Even if they don't appear to drastically shape you, your foundation garments (including bridal slip and Spanx) WILL affect the way the dress hangs on your figure. You don't want to end up with a different fit on your wedding day because of a different bra. Depending upon the cut of the dress, wearing the wrong bra can even affect whether the hem hangs evenly. If you're not able to get shoes you want before your fitting, wear shoes at the same heel height as your intended purchase and have the hem marked for the next fitting, when you can bring the pair you'll actually wear.

Don't trip. No, really. If you aren't confident in your ability to glide everywhere with ease, get your hem taken up to about 1" from the floor. You'll be at a heightened anxiety level on your big day, and you want to ensure you can remain effortlessly glamorous throughout it. If you are wearing a long veil, I recommend trying it on with your dress to make sure the hem of the dress and the fall of the veil correspond.

Get fitted later than sooner. Have your fittings -ideally, three- scheduled within two months of your big day. Fitting done too early means that whatever weight you gain or lose during your planning process won't impact the fit of your dress too greatly. No one wants to be mainlining fried chicken (or the Master Cleanse!) during the most exciting time of their betrothal because they jumped the gun. Your last fitting should be two weeks before your wedding so any problems that arise have enough time to be corrected.

Courteous brides get the best fits. It should go without saying, but arrive for your fitting clean, gum and beverage free, and polite. Your tailor will appreciate it. Try not to move around too much while they are pinning: it ensures the most accurate fit and keeps you from getting stuck. Listen with an open mind to their recommendations about your dress- they are professionals who are intimately familiar with garment construction, and may know of a better way to make the look match your vision. You can get a second opinion after the fact, but hear them out.

Take your posse. Have your mom, maid of honor, or a close friend come with you to at least two fittings, especially the final fitting. They bring a valuable second pair of eyes to the gowns' fit, and spot any problem areas you or the seamstress hasn't spotted. They will also be able to find out how to best zip, lace, and bustle your gown from the experts, so it can be replicated correctly on your wedding day. If no one can accompany you, ask for the directions to be written down.

Test the fit. You want to be able to dance, sit, hug, and walk on your big day. After the dress has been pinned to you and you're given the all clear to leave the pedestal, take a minute to get down and move around so you can let the seamstress know if adjustments need to be made.

I hope this advice allows you to have the best experience possible and find quality, one-on-one service. Happy fitting!

Aria M. Mason is the daughter of a bride who made her dress without a pattern, the niece, granddaughter and great granddaughter of modistes, a three time MOH, and has been sewing costumes and gowns for nearly 20 years. You can learn more about her at www.ariamason.com. (This article initially appeared in NOLA Wedding Guide Magazine in the fall 2013 issue.)