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.
For me, the best way to promote products and links is thru social media. Posting in Facebook and Twitter is very effective way I guess. And also posting in this forum will do. But it depends on the product you will sell. It must be genuine and legit. And promoting a product must have a good HOOK,LINE, and SINKER quality, meaning it has best and good promoting strategy.