A microphone connects to a jack through a series of wires that transmits the audio as electrical signals. You can rewire a plug-free end of a monophonic microphone to a headphone jack to enable the mic to plug into a 3.5mm input socket. You will need tools that are found in most homes. The headphone jack can be acquired from a hardware store or hobby shop. You must have adult supervision if you are underage, since a soldering iron is used.
Put on work gloves to protect your hands. Place the soldering iron on a work surface and plug it in. Let the soldering iron heat up for six minutes.
Make a 4-inch slit in the insulation at the end of the microphone's cable using a utility knife. Pull the two sections of cable apart, using your hands. Cut 3 inches of insulation from the ends of each section, using the utility knife. Pull the wires out from inside the ends of each section.
Twist the bare copper wire that is in each section between your fingers so that each forms a rod. Twist the two copper wires around each other.
Strip half an inch of insulation off the ends of each of the insulation wires coming out of each section, using a wire stripper. Twist each wire around, using your fingers, so it forms a rod.
Unscrew the front section of the headphone jack from the back section. Run the wires from the end of the microphone cable through the hole in the back section of the headphone jack.
Apply a drop of solder to the end of each wire. Let the solder cool for a minute. Run the copper wire through the hole at the end of the front section's lug. Hold the wire against the lug. Apply the tip of the soldering iron to the wire for four seconds. Let the solder cool for a minute.
Place the exposed end of the yellow wire against the hole in the lug that is closest to the front. Apply the tip of the soldering iron to the wire for four seconds. Let the solder cool for a minute.
Place the exposed end of the other wire into the hole and against the contact at the center back of the section. Apply the tip of the soldering iron to the wire for four seconds. Let the solder cool for a minute.
Screw the two sections of the headphone jack back together. Unplug the soldering iron.