You will need to locate a space to fit it.
Most new car radios come with a mounting bracket that the radio just slides into.
You will also need to locate 1 permanent live feed for the radio memory, and a switched live feed for the actual power, although the permanent can be combined with the switched if you're not bothered about losing your tuned in stations.
A good bet would be a visit to Halfords and pick up a plug which fits directly into the radio and has wires coming out to allow you to make the connections.
You also need to locate a good earth (or negative) point.
You also need a minimum of two speakers the speakers must be connected as shown in the radio installation manual . Do not be tempted to combine the speaker negative leads.