I am looking for the fastest and cheaper way to get traffic to my site
Go to the solution
Try Paid marketing ($5/day)
This is an accepted solution.
I think you should consider to deploy Paid advertising( Facebook ads, Google ads). This method is the best way to boost your store trattic.
Two guides below would be useful for you:
+ A Comprehensive Guide To Using Google Adwords
+ Shopify Facebook Ads: The Complete Guide for Beginners
Hope it helps!