I personally wouldn't do this myself.

If your confident all the best.

You will need a headunit which supports the steering controls.

You will need trim removal tools.

You will need knowledge of electronics

I would just save myself the hassle and pay a professional to do it.

Please solder and use oxygen free thingos that you melt onto the exposed wiring.

Hard to believe but 1/10 cars burnt, is due to faulty wiring in their sound system.