This is a very quick and easy way to make a heating pad. All you need is a zip-lock freezer bag, and some uncooked rice. Make sure the freezer bag is microwave safe, if not it'll melt and smoke and be a disaster. If you have just found a freezer bag around the kitchen and aren't sure if it's microwave safe, don't use it.
 Once you are certain you have a bag you can use in the microwave, pour in some rice. Fill the bag so that it is about three quarters full with uncooked rice and then secure it with the zip-lock across the top., Warm it up in the microwave for a minute, adding another seconds to a minute if necessary. Once it is heated up, take it out out the microwave and wrap it in a hand towel or other piece of insulating fabric.You don't want to put the heated bag directly onto your skin.
Grab a zip-lock freezer bag.
Pour rice into the bag.
Pop it in the microwave.
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