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Although you’ll take precautions to limit the number of materials that escape and fly around, you’ll want to protect yourself. Wear goggles, a face mask, and sturdy gloves. Wear long sleeves and pants to avoid leaving any skin exposed to potentially hazardous materials. On a surface you don’t mind denting (a garage floor, a carport, etc.), lay out an old towel or blanket. You may wind up having to throw this item away, so make sure it is not a new or favorite item.  The thicker the fabric is, the better. Ideally, the fabric will be able to remain intact when faced with glass, jagged metal, and other broken parts. A solid wool or cotton throw will work well, while you should stay away from linen. Once your stage has been set, grab a sledgehammer. A sledgehammer will be easy enough to wield and heavy enough to damage all of the complex components that make up your computer. Sledgehammers come in various sizes and weights. If you are nervous about holding a 10-pound (160 oz) hammer, you can likely find a 3-5 pound (48-80 oz) one at your local hardware store. Place your computer in the middle of the towel or blanket, keeping it as far away from the edges as possible. This will help keep all of the broken components contained once you’ve gotten started. Place a second blanket or towel on top of your computer, lining the edges up with the bottom fabric as much as possible. This fabric, too, should be something you have no desire to save, because it may need to be thrown away. If you have one thin blanket and one thick, place the thicker one on top. A thin blanket or towel may unravel if it is hit directly with a sledgehammer. Now the fun part! Begin hitting the computer through the blanket with your sledgehammer, covering every possible inch. Keeping your arms, legs, and face protected, continue hammering until your computer is audibly and visibly destroyed. Once your computer has been destroyed, make sure you properly dispose of all of the pieces. Batteries, for instance, should never be thrown in your dumpster, but should be disposed of according to your city’s codes. Electrical parts are similarly tricky, and should be handled with care.  Most municipal sites have information regarding disposal practices. You can also contact your city or county’s waste management department for disposal instructions.

Summary:
Use protective gear. Lay out an old towel or blanket. Set aside a sledgehammer. Lay the computer on the blanket. Place a second blanket over the computer. Hit the computer through the blanket until every piece is broken. Clean up after yourself.