First and foremost, do not attempt to clean your dress yourself. Dresses are made out of a variety of materials and some react well to usual cleaning methods and some do not. Some dresses will stain just from water, so you must be careful! Some dirt can be softly brushed from the dress, but do not try to wash it with any type of liquid or spot remover.
Second, find a trusted dry cleaner. It’s a great idea to do this before the wedding anyway so you know who to take the dress to after the wedding. Cleaning can be expensive, but please don’t choose the dry cleaner just off price. They need to be experienced and some will offer great packages if you use them to preserve the dress as well. For example, Andrea Porter with Circle Park Bridal recommends Pinstripe Cleaners located in Denton, Texas. While they are a little expensive, they do an amazing job on hard to clean gowns. A perk to using Pinstripe Cleaners? They include a free cleaning between the bridal portrait and the wedding if you get their preservation package.
Speaking of preservation, most dry cleaners and bridal gown stores offer preservation services. For gowns that are relatively clean, this gown preservation service is a great option and relatively inexpensive. The dress is shipped off to a cleaner and preservation specialist and shipped back to you in see through box so you can see your preserved gown. This allows you to keep your dress for future generations if you choose.