Content-Delivery Networks (aka CDNs) are a great way of speeding up page delivery across the world. Google and other search engines are inherently concerned about the speed of your site and page content. Use Amazon's AWS, MaxCDN or any number of other tools out there to leverage CDNs along with browser-caching tools like W3 Total Cache, WP Super Cache and others.
Clearly, paying for ads and other initiatives is always one method to drive traffic to your site or blog. If you have a small budget, and you track things properly, you can come up with a cost-per acquisition (CPA). If your CPA is high enough, you can comfortably scale your advertising revenues. Be sure to implement things like Facebook and Google tracking pixels to determine the effectiveness of your ads.
Social media is one of the most popular free marketing tools around, and plays a role in driving traffic to your website. Use Facebook, Instagram, and LinkedIn to promote blog posts and other useful pages on your website. This way you can turn your social media audience into website visitors, and draw traffic from their networks if you post shareable content.