Hi guys

I just bought and installed a sony CDX GT540Ui to replace my original RCD300. But I've had a few issues with it. Firstly it doesnt power up or turn off with the ignition. Have i missed a connection or something? The signal on the radio is also a bit rubbish but i've been told that might be beacuse I didn't connect the aerial to a 12v connection. To be honest i don't know what the 12v connection is and how to connect it
This is the first time i've tried to install my own radio so any help is much appreciated.