"The best way" is different for everyone. Some may want the cheapest option (AUX in), some may want to spend more money for a more integrated option. I chose the Dice Mediabridge with Bluetooth (even though I already had Bluetooth for calls-I don't use it) because I can step into the vehicle, start playing music with my iphone without physically connecting it, and change songs on the steering wheel. I lost my CD changer by doing this, but all that means is if I buy a CD I have to wait until I get home and convert it before I get to listen. It has definitely not been flawless (actually quite buggy sometimes) but 90% of the time it is worth it to me. This option still gives you USB and Aux connections.

Scott