Start off with a site such as chaturbate, you will make money from their audience.
Unless you have your own audience, you will have no one watching you have sex with random guys....
Build your own audience, then move to your site. You still get paid on chaturbate, but not as much as you will on your own site.
Social media is everything in this game, you could also do well with your own pornhub channel. This will again help you grow an audience.
A twitter account posting naughty stuff and instagram will also help you grow this audience.
It's a lot of work, don't expect to be making money from this as the market is flooded and only a few actually take off and end up earning good cash, but give it a try. You don't know until you do it.