fitting new head unit to exsisting amp

[danny78]

Hello can anyone help me as I am struggling to fit my new sony head unit to my passat 2.5 v6 tdi. I have removed the exsisting cd multichanger as it broke but I still have the standard amp. I bought the passat connector from halfords but the speaker connector doesnt match up on the car there was two small plugs one yellow and one blue I havent got a clue how to connect it up so I get sound. Please help!