As the owner of a wordpress site with more than 5 years of experience, I would like to share some tips with you below. The first and most important thing is to target an audience that is from America, Canada, etc. The second thing is to write quality content. Also, a very important thing is that the site looks simple and is functional and fast (I got the speed when I switched from shared hosting to cloud hosting - which I advise everyone). Another very important thing is to find a good ad network that has a good CPM. I came across Monetag ad network and I can tell you that they have a very high CPM compared to other ad networks. I mostly use the Interstitial type of ads because I make the most money from them, but I recommend everyone to test different types of ads and decide for themselves what to use on their site.