What matters more is the process.
I'm hesitant about writing a long, proper response for a question like this these days, because half the time no one is willing to bother (or has the time) to do things "right". In any case clay barring won't do anything for the swirls, but it is the first step.
The short answer about how I would do it (the right way), would be to wash, clay, wash, use a dual action polisher with a polishing compound, wash, dual action polisher with a glazing compound, sealer, caranauba wax. This is something you can or should do one every 2 years or so, so it's worth doing it right. It's scary how soft and smooth it feels after doing this. The trick is the dual action polisher which removes the swirls. Anything else and you'll just be creating new ones.
Anyway, if you have a more specific question on what you're actually willing to do, then let us know.
I'm hesitant about writing a long, proper response for a question like this these days, because half the time no one is willing to bother (or has the time) to do things "right". In any case clay barring won't do anything for the swirls, but it is the first step.
The short answer about how I would do it (the right way), would be to wash, clay, wash, use a dual action polisher with a polishing compound, wash, dual action polisher with a glazing compound, sealer, caranauba wax. This is something you can or should do one every 2 years or so, so it's worth doing it right. It's scary how soft and smooth it feels after doing this. The trick is the dual action polisher which removes the swirls. Anything else and you'll just be creating new ones.
Anyway, if you have a more specific question on what you're actually willing to do, then let us know.