Set each dial to the central position. This provides a neutral starting point.
Turn on the equalizer. Turn on the CD player or MP3 and select a track with which you are familiar. Using a familiar track is preferable because you know already how it should sound.
Hit "Play" on the CD player or MP3 player and begin moving the dial governing the lowest frequency range. Turn it clockwise to increase the prominence of the frequency and counterclockwise to reduce the prominence of the frequency. The name of this dial varies according to the brand of equalizer you are using. Typically this dial is called "Bass," "Low" or "Low." Turn it up so the lowest frequencies become prominent, creating a solid bass foundation. If the sound becomes "muddy" or "boomy" reduce the frequency strength.
Tweak the next dial to the right, or below. Frequency dials are typically arranged left to right or from low to high. The next dial, depending on the sophistication of your parametric equalizer, will either govern the entire middle range, or the low middle range. Some parametric equalizers split the middle into two. Adjust this dial so there is a satisfying balance of low and middle frequencies. If the drums and guitars sound weak during playback, it is likely because this frequency is too low, or the bass frequency is too high.
Adjust the remaining dials to your preference. Once you've adjusted each dial, make fine-tuning adjustments. You can make improvements to the sound of your home audio system by "ducking" a frequency as well as by boosting it. For example, if the vocals are sounding too high or "tinny," reduce the "Treble" dial to mellow them. What you reduce is as important as what you increase.
Set each of the slider dials to the center of the slider groove, where it says zero. A graphic equalizer has a zero point for each frequency. This point is located in the middle and represents the neutral level. On some models there is a notch at zero which enables you to find the neutral point more quickly. Move the slider below zero to cut it and move the slider above zero to boost it. A graphic equalizer functions in a similar way to a parametric equalizer, it just has more dials.
Adjust the lowest frequency, using the left-most slider dial.
Work your way through each frequency, moving the sliders up and down. If an adjustment makes the audio sound unpleasant, reverse it.