One traditional way of reusing a wedding dress uses the fabric from the skirt and train to create a baby's christening gown when the first child of the marriage comes along. Since few brides wear their mother's wedding gowns, a custom-made christening gown repurposes the fabric in an appreciated way. Create a christening gown out of the white or ivory fabric from a wedding dress as a gift or for your own child.
Turn the wedding gown inside out.
Rip the seam between the bodice and the skirt using the seam ripper, separating the skirt from the bodice. Detach the train. Set aside the bodice and train. If there is an attached lining in the skirt, rip the stitches holding it to the skirt and set it aside. Open a seam in the skirt so that you have one long, flat piece of fabric.
Lay out the pieces of the pattern on the skirt fabric as shown in the pattern's instructions. Align the bottom of the hem of the wedding gown with the bottom of the gown pattern so that the trim on the wedding gown skirt becomes the trim on the bottom of the christening gown.
Sew the christening gown according to package instructions. You will not need to hem the bottom, since the bottom of the wedding gown becomes the bottom of the christening gown.
Add purchased trim around the sleeves and neckline as desired. Coordinate purchased trim to the detail on the wedding gown for best results.
Use the fabric from the lining to create a slip for the christening gown. Cut a bonnet or bootees from the bodice, or use the train to make a blanket or if you need extra fabric.
Attempt this project only if you're an experienced seamstress to avoid ruining a wedding dress with nothing to show for it.