Social media is not totally shit, you still can promote on facebook group and on instagram. It's depend on what products that you sell though, if you sell like cosmetics product, you can join a facebook group about cosmetics and you also can endorse somebody on instagram to use your products.
Strongly agree with your opinion, the promotion on social, especially Facebook and Twitter if the exploit will be extremely effective. You can post on product groups or build your own community on Facebook or Twiter, which will be a very effective promotion channel if you know how to use it.
That's right - all it takes is one post that's shared by one person to go viral and you can get your promotional message across to thousands of people around the globe without any financial outlay.