6 edited in mnemonic, which apparently went over the head of the person who edited it out)
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Red is for Right. Blue (or green) is for Left. Copper is for ground (I remember this with the mnemonic Red Right bLue Left Copper Common). All 3 are coated in a lacquer you need to burn or scrape off before you solder. With standard headphone plugs, with the plug facing away from you, the right pin is right, the center pin is ground, and the left pin is left.

  1. Common (or "ground")
  2. Right
  3. Left
  4. Insulating ring

1ground 2Right 3Left 4Insulating ring

Red is for Right. Blue (or green) is for Left. Copper is for ground. All 3 are coated in a lacquer you need to burn or scrape off before you solder. With standard headphone plugs, with the plug facing away from you, the right pin is right, the center pin is ground, and the left pin is left.

  1. Common (or "ground")
  2. Right
  3. Left
  4. Insulating ring

1ground 2Right 3Left 4Insulating ring

Red is for Right. Blue (or green) is for Left. Copper is for ground (I remember this with the mnemonic Red Right bLue Left Copper Common). All 3 are coated in a lacquer you need to burn or scrape off before you solder. With standard headphone plugs, with the plug facing away from you, the right pin is right, the center pin is ground, and the left pin is left.

  1. Common (or "ground")
  2. Right
  3. Left
  4. Insulating ring

1ground 2Right 3Left 4Insulating ring

5 added 29 characters in body
source | link

Red is for Right. Blue (or green) is for Left. Copper is for ground. All 3 are coated in a lacquer you need to burn or scrape off before you solder. With standard headphone plugs, with the plug facing away from you, the right pin is right, the center pin is ground, and the left pin is left. 1ground 2Right 3Left 4Insulating ring

  1. Common (or "ground")
  2. Right
  3. Left
  4. Insulating ring

1ground 2Right 3Left 4Insulating ring

Red is for Right. Blue (or green) is for Left. Copper is for ground. All 3 are coated in a lacquer you need to burn or scrape off before you solder. With standard headphone plugs, with the plug facing away from you, the right pin is right, the center pin is ground, and the left pin is left. 1ground 2Right 3Left 4Insulating ring

1ground 2Right 3Left 4Insulating ring

Red is for Right. Blue (or green) is for Left. Copper is for ground. All 3 are coated in a lacquer you need to burn or scrape off before you solder. With standard headphone plugs, with the plug facing away from you, the right pin is right, the center pin is ground, and the left pin is left.

  1. Common (or "ground")
  2. Right
  3. Left
  4. Insulating ring

1ground 2Right 3Left 4Insulating ring

4 screaming image reduced to civilized size; edited body
source | link

Red is for RIGHTRight. bLueBlue (or green) is for Left. Copper is for ground. All 3 are coated in a lacquer you need to burn or scrape off before you solder. With standard headphone plugs, with the plug facing away from you, the right pin is right, the center pin is ground, and the left pin is left. 1ground 2Right 3Left 4Insulating ring 1ground 2Right 3Left 4Insulating ring

1ground 2Right 3Left 4Insulating ring

Red is for RIGHT. bLue (or green) is for Left. Copper is for ground. All 3 are coated in a lacquer you need to burn or scrape off before you solder. With standard headphone plugs, with the plug facing away from you, the right pin is right, the center pin is ground, and the left pin is left. 1ground 2Right 3Left 4Insulating ring 1ground 2Right 3Left 4Insulating ring

Red is for Right. Blue (or green) is for Left. Copper is for ground. All 3 are coated in a lacquer you need to burn or scrape off before you solder. With standard headphone plugs, with the plug facing away from you, the right pin is right, the center pin is ground, and the left pin is left. 1ground 2Right 3Left 4Insulating ring

1ground 2Right 3Left 4Insulating ring

3 improved explanation
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2 replaced "copper is green" with ground, and added the fact the cables are covered with laquer
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1
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