Who told you forum and social media is useless? I think your marketing materials is not attractive. Another factor is the niche, if you post bitcoin related ads to food, or celebrity no one will click your ads.
Which is the best way to promote products or refferal links? Social media and forums is total shit,no one interested in this.
In this world or rather this time many of us are using phones and laptop. We are surfing the internet and using social media like facebook and twitter. For me, the best way to promote are links because those people who you can talk about this is also your friends specially on facebook. You will ask them to click this or that and they will do it. They will do your instructions without hassle. Inshort it is one click away. And it is the best way to promote.