Exactly, @kindsvater! The best tactic for promotion will vary depending on what it is that's being marketed and the target audience for it.
@Joshvin23, you need to understand that not everyone will buy from you the first time they hear of the product you're marketing, so you want to find a way to have ongoing contact with them. To do this, you need to know where they spend their time online, and what channel(s) they prefer. A lot of people like to say that email is dead, but it turns out that it's surprisingly effective, so collecting their email address might be a good place to start. But that might be different for your audience, depending on who they are and how they spend their time online.
Some kind of content marketing initiative might be a good way to collect contact information or to get people to return to you time and again. Blogging, podcast series, white paper or report series, webinar series, etc. Whatever works for your audience and that you're comfortable providing. The key is to keep at it. A "one and done" blast approach will likely not provide the kind of results you want.