1 - Connect the wires together in a connector block.
2 - Push the CD lead onto the connector pins - make sure :
a. The one wire on its own (out of the 3 on the CD lead) goes over the pin closest to the aerial on the stereo
b. It fits firmly in place
3 - Slide the grey cover back over the plug
4 - Pull the plastic handle back over the connector so its held firmly in place