control panel, sound, advanced.
Options, turn on Advanced controls.
Options, properties, recording.
adjust the recording settings and enable the microphone, click ok and set the mic volume levels.
you might want to turn on the Mic Boost option - most PC mics require that.
Pro Audio mics with a Pro mic interface do not.
when you open up the speaker icon in the system tray again, you might want to mute the microphone (playback). when doing communications, if it goes over the speakers, it might cause feedback.