welcome to the forums mate, this should really be another section, but anyway.
it depends on how much you want to spend,
if you want it to look good, the first thing i would do is lower it and take the rear spoiler off (trust us, it looks unreal) then a nice set of wheels to match the style of the car (ie not chrome dolce's)
to sound good ? lol, well id prefer it to go better
, what you can do is maybe
invest in a 2.5 catback with a decent muffler (cannons will make a fart noise if not turbo)
you can get some extractors and just have engine noise heh
cold air intake (give it a strong roar on WOT)
stage 3 chip to make it go better
where you from ?