Start by selecting speakers for your car. Make sure to pick speakers that fit your needs and will fit your car. Once you're ready to install, remove the panels surrounding the speakers in your car and remove the factory speakers from the wiring harness. Then, connect the new speakers to your car's wiring and install.

If you are not technically minded, you can simply measure the cavity in your vehicle and if it matches those dimensions, you have a single DIN and you need a single DIN universal car stereo. However, some vehicles have a double-DIN.

If you have a low-powered factory stereo (typically 10-15 watts RMS per channel or less), speakers with high sensitivity ratings (over 90 dB) will make the best match. If you have a high-power system like an aftermarket stereo or external amplifier, then consider speakers with lower sensitivity ratings.

Start by setting the crossover points according to your speaker and subwoofer specifications. Play a song with a variety of music genres and listen to how the different frequencies are distributed. Adjust the crossover points until each component is handling the frequencies that it's designed to handle.