How to Fix a Sweater That Has Stretched
To fix a sweater that has stretched, you'll need to soak the stretched parts in boiling water and stretch them back. Start by boiling a medium-sized pot of water, then pour it into a large bowl. Put on some protective gloves to protect you from the hot water and steam. Then, dip the areas that need reshaping, like the sleeves, cuffs, or neck, into the boiling water. Once you've dampened the right parts, lay your sweater on a flat surface. Using your fingers, pinch and squeeze the material to the right shape. When you're happy with the shape of your sweater, dry it with a hair dryer to help it keep its new shape.
Determine how much of a sweater needs reshaping. You only need to soak an entire sweater if you want to shrink it entirely. Sometimes, this is not necessary. Your sweater may only have certain portions, like the neck or sleeves, that have stretched out. In this case, you can reshape the sweater by hand. Wet the sweater and remove excess water. Fill a tub with slightly warm water. Submerge your sweater in the water until it's soaked. Remove the sweater from the water. Press out any excess water into the sink. Do not wring or squeeze the sweater to remove water as this can cause damage. Reshape the sweater. Place the sweater between a padded towel. Using your hands, gently mold the sweater into your desired shape. Then, set the sweater aside to dry. Dry carefully. You should not hang a reshaped sweater to dry. Hanging can cause bumps and lumps on the sweater's shoulders. Instead, pin the sweater to the towel you were using. From there, lay it down in a safe place to dry. Keep out of reach of children or pets as you do not want the sweater handled while drying. Wet your sweater. If you want to reshape the whole sweater, more extreme action needs to be taken. To start, get your sweater wet using lukewarm tap water. How wet you get the sweater affects how much it shrinks. For more shrinking, completely soak the sweater prior to drying. For less shrinking, just gently mist the sweater using a spray bottle until its damp. Place the sweater in a dryer. If you want to shrink a whole sweater, you can use a machine dryer. After wetting the sweater, place it in a dryer on high heat. You should use the highest heat setting possible, especially if you want to shrink your sweater significantly. Run the dryer until the sweater is completely dry. This should shrink your sweater a couple of sizes. Prepare a basin of water. You can shrink sections of a sweater, like the neck or sleeves, if only these areas are stretched out. Be sure to test a hidden section of your sweater first, as either the boiling water or the blow-drying may affect the color. Boil a medium-sized pot of water. Then, pour this water into a bowl. Dampen the areas you want reshaped. You can dip the sleeves, cuffs, or neck of the sweater into the water. Use protective gloves if the water is still steaming. You do not want to get burnt in the process. Remold the sweater. Using your fingers, gently pinch and squeeze the portion of the sweater you're shrinking. Work the sweater until it's at your desired size and shape. If you're remolding the cuff of a sweater sleeve, it might be a good idea to hold the cuff chest level as you remold. As the cuff is small, pulling it closer will allow you to see what you're doing. When remolding a larger area, like the neck of a sweater, try laying the sweater down on a flat surface as you work. If your sweater is very wet, you may want to remold it over a towel to catch any drips. Dry with a hair dryer. When you've reshaped the sweater, take a hairdryer and blow the sweater dry. The hot air works in combination with the hot water to solidify the new shape, shrinking that portion of sweater back to its original size. As the method requires hot air to work, you do not want to use the cool setting on your hair dryer. Start with the low heat setting. If the sweater is not drying fast enough, consider switching to high heat. Fold sweaters rather than hanging them. You should fold your sweaters and store them in drawers rather than hanging them. Hanging sweaters can stretch out portions of the sweater. It can also leave small humps at the shoulders. If possible, fold your sweaters rather than hanging them. Take precautions if you must hang sweaters. If you need to hang your sweaters, take certain precautions. Use thick, padded hangers to provide more support. This can help prevent stretching. You may also want to fold your sweater over and hang it from the bottom bar of a hanger. The bottom bar may provide more support, preventing stretching. You can cut open an empty paper towel tube and then fit it over the bottom bar of a hanger. This may help prevent creasing. Hand wash your sweaters. If possible, you should always hand wash your sweaters. Hand wash them in cold water with a small amount of fabric softener and detergent. Rinse thoroughly, making sure to get all the suds out. When removing excess water before drying, press the sweater. Do not squeeze or wring it. Fold the sweater in half and hang it over the bottom bar of a hanger on a drying rack to dry. 
Determine how much of a sweater needs reshaping. Wet the sweater and remove excess water. Reshape the sweater. Dry carefully. Wet your sweater. Place the sweater in a dryer. Prepare a basin of water. Dampen the areas you want reshaped. Remold the sweater. Dry with a hair dryer. Fold sweaters rather than hanging them. Take precautions if you must hang sweaters. Hand wash your sweaters. 