- Google/Facebook/Reddit/Twitter ads
- Find an influencer/blogger, have them talk about your site (assuming it meets their niche) in exchange for either the product or money
- Write an article that makes it to the Hacker News front page (not sustainable, but a nice dopamine hit)
Worth noting that not all traffic is the same - you'll find it significantly easier to increase conversion rates on the traffic you already get, than to get additional traffic.
rozenmd makes a good point with search/social ads
Or posting to HN, /., Reddit, LinkedIn, etc and hoping for the best
But ... without knowing what kind of traffic you want, recommending any specific path is going to be a bit of a craps shoot :)
Is this for a business? Personal website? Something else?
If it is a business, is it a new business, or an existing one? What kind of business - getting a bunch of traffic to your landscaping business in Acapulco is not going to be especially helpful if it is all coming from Lagos
What are you hoping to gain by getting "traffic fast"? Name recognition? Bragging rights? Sales?