I might be wrong, but isn't having a porn sig against the TOS here? But, to answer you question, there is no best way. If you want to succeed you either have to either have excellent & unique content, a killer affilate program with excellent conversions and payouts, or be great at SEO. If you are lacking on all 3 you are going to have a hell of a time in that industry.
actually it's easy to do SEO services on an adult site. You just have to be prepared to shell out some money for ads and you must have some friends from adult authority sites.
I think it is harder to get a good rank for a particular keyword or key phrase in adult industry since almost all Adult SEO's are using black hat, but I'm not sure still..