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Cotton is characteristically easy to wrinkle; starch can prevent wrinkles, stiffen material and help prevent liquid stains. Starching your laundry can be done either in bulk with an in-wash starch or individually with spray starch products. Before you attempt to starch your cotton flannel shirt, read and follow the directions printed on your starch product.
Read the garment care label and ensure that your cotton flannel shirt is machine washable.
Place your laundry in a washing machine. For best results, set the water temperature to warm or hot. Add detergent and allow washer to cycle to the rinse cycle. Spray starch is an effective alternative for shirts that require cold water washing.
Stop the machine when the wash reaches the rinse cycle. Open the door and add 8 ounces of starch for a medium starch or 4 ounces for a light starch, if doing a full load. Close the door and allow washing cycle to finish. To starch a single shirt in a small load, test a small amount of in-wash starch and increase until desired stiffness is attained.
Place your clean, starched shirt in the dryer. When drying is complete, neatly fold or hang your shirt.
Read the garment care label on your flannel shirt to determine fabric content. If your shirt is 100 percent cotton, set the iron to the cotton heat level and allow it to preheat. If your shirt is a cotton blend, set the iron to the appropriate corresponding heat setting.
Lay the clean flannel shirt on an ironing board or flat heat-resistant surface. While holding the can in an upright position, spray starch on the shirt evenly from an 8-inch distance.
Apply the hot iron to the shirt, smoothing out all wrinkles. Do not allow the iron to rest for long periods on your shirt, as it may scorch the fabric. Fold or hang your shirt.
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