What could be some good ways to promote an exchange service like Changelly? How to become noticed here?

Could you guys name some efficient methods? I know that there are signature campaigns, but not sure if they are efficient to get customers. I think when the users see such a campaign they reflectively think: "aha, that is an ad, not interested". Or maybe I underestimate it, I don't know.

I'm thinking about a referral program, so that users could benefit by inviting the others. In my opinion referral programs can be useful.

Could you guys name some other efficient methods?  Maybe someone could point to some good promotion examples here at bitcointalk.