Plug the amplifier into a live electrical socket. Make sure that the amplifier is turned off.
Turn down all of the volume and gain knobs on the front of the amplifier so that you do not blow your speaker when connecting your guitar.
Using a standard 1/4-inch patch cable, connect the guitar to the amplifier by plugging the ends of the cable into the inputs of the amplifier and the guitar. Check that the volume and tone knobs on the guitar are turned to "0."
Turn the amplifier on. Once it is powered up, turn the volume and tone knobs on the guitar to their maximum volume.
Turn all of the treble, bass and gain knobs on the amplifier to their neutral position. On most amplifiers this means that the line on the knobs are facing straight up, or in a "12 o'clock" position. Be sure to leave any effects knobs, such as reverberation or delay, in the "Off" position.
Turn the volume knob on the amplifier to "2" or "3." Do the same with the gain knob. Strum the guitar and a clean tone will be produced.
Adjust the volume to a desired level and make a note of the position of all the knobs on the amplifier. Their final positions will produce the best sound for your amplifier.