Social media is all about the content and if you have unique content then stat your works. Share once it would spread by own if it not then there is problem in content or you have shred at wrong place.

First thing is content and then is proper audience.

for traffic you sould to PPC or social media traffic

you can increase your traffic with social media like facebook,twitter and also you can increase with pay per click.

Off Page SEO is the best way to drive huge traffic

I think Forums sites can be a great use. When you go to forum with huge visitors and give have a signature link on your profile. It can bring more traffic from the forum. But you must be a regular and a popular user in that forum.

You can buy website traffic from freelancers on sites like SEOclerks, listingdock etc.

you can use sem or ppc.