How to drive cheap paid traffic to website

Hello bloggers, I have been wondering and making research thoroughly if I could get a good source that I could drive safe traffic to my website monetized with Google Adsense, but I couldn't get a reasonable result.

Many bloggers are actually finding it very difficult to get traffic to their website or blog.

Apart from Facebook and Google AdWords, is there another source that is safe to drive traffic to websites monetized with Google AdSense that complies with their program policies?