Blot fresh stains with damp baby wipes. If the compound has not set in, the chemicals in ordinary baby wipes can help remove both the oils and the dyes found in most commercial self-tanners.
Remove the dress and turn the garment inside out. Hold the discolored fabric beneath a stream of cold, running water to wash out as much of the tanner as possible.
Pour 1 tsp. baby shampoo over any discolored areas. Rub the material gently to work the shampoo into the oily portion of the stain, wait 5 minutes, then rinse.
Mix ¼ C. oxygen bleach or all-fabric bleach into 2 C. cold water. Pour the solution over any lingering stains until the fabric is totally saturated. Wait 10 minutes, then rinse in lukewarm water and repeat, if necessary, until the tanner is no longer perceptible.
Soak persistent or lingering stains in denatured alcohol, then drench the affected area in liquid dish soap and wash according to the garment care instructions. Inspect the garment once the wash cycle is complete, if any portion of the stain is still in evidence, repeat the cleaning process. Do not dry the dress until the tanner has been totally removed.