How can I increase the horsepower on my Audi A4?

I want to add more power to my Audi A4 but I'm not sure where to start. What are some modifications I can make to increase the horsepower and performance of my car?

One option is to upgrade your engine's air intake system. This will allow for more air flow and increase the efficiency of your engine, resulting in more horsepower.

Another way to increase horsepower is by installing a performance exhaust system. This will reduce back pressure and allow for smoother air flow, resulting in more power.