Not only are tangled extension cords almost impossible to use, failure to properly coil a cable can cause permanent damage to the conductors and even cause a fire hazard.
The secret is to always work form the same end and always push that end back through the closest loop. Never pull it.
Once you get four or five feet of the cable untangled, go ahead and coil it. This makes quick work of pushing the cable back through tangled loops as the untangled end gets longer and longer.
Once you have several feet coiled, hold that in one hand while you gently flip the tangled end to work the kinds out of it.
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