Hand-wash the top according to the manufacturers directions listed on the interior label. Most sequin tops cannot be tossed into the washer because you run the risk of the sequins loosening and falling off. Once the top is washed, lay flat to dry until it reaches a damp consistency.
Hang the top in a bathroom while you shower. If you are not showering, then turn the shower on to the hottest temperature and close the bathroom door. The steam from the shower, combined with the dampness of the top, will reduce the wrinkles. Let the shirt steam for 15 to 20 minutes. When complete, turn the shower off and transfer the shirt to a room with no moisture for it to finish drying.
Steam the wrinkles out with a professional steamer if you do not have time to wash, or there are still visible wrinkles. Set the steamer to a mid-temperature for heat. You do not want to set it to the hottest setting because this may cause the sequins to melt or disfigure. Hold the steaming wand four to six inches from the sequins and slowly steam out the wrinkles.
Turn the shirt inside out so the back of the sequins are facing upward and lay flat on an ironing board. Set a iron to a cool setting. Place a dishtowel onto the back of the sequins. Glide the iron over the dishtowel in 10 second increments. The cool heat from the iron will help remove small wrinkles in the material. Do not place the iron directly onto the sequins.