It depends on your unique situation and preferences. Myself, I run a webmaster forum - and assuming it ever gets big, I want to get cash via classified ads. Basically, the huge traffic would attract ad buyers - who would pay to bump their threads, like what is done on DigitalPoint.com.
Anyway, for my drum lesson website, my mode of profit would be via the Patreon page. Basically, it would contain mostly free stuff - but also a lot of advanced content - available only via subscribing.
O.K., regarding all of this, two things to keep in mind are:
- People don't like ads, generally (unless they are sort of in-direct).
- They don't like pushy selling.