I would stick clear of the social media paid advertising unless you have deep pockets, as its not very helpful or useful unless you invest thousands into it. Facebook tends to send illegitimate traffic 99% of the time (from our results) so it's a complete waste. And if you google about it, you will see others say the same. I'd suggest banner or text advertising on sites where there are people who would have interest in your services. As for free marketing, just post around on forums and help people. They will see your signature and sometimes turn into a sale.
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