How to earn Money online from Adsense

I am sure Adsense is the best way to earn money online. Though there are a lot more stuffs to make money online, adsense is the most trustworthy and a large set of people use Adsense. However the truth is not many people earn money from Adsense. Mere having a blog and adsense account doesn’t help gain Money.
Note that to earn money from adsense, traffic is not most important. More than traffic the page rank of the Blog is important. But what is Page Rank?
Page Rank is the rank given by Google based on the content and number of links the blog has. The Page Rank 1 is the starting rank to rank your blog. The blogs with page rank 10 are the best and its utmost difficult to get page rank 10. Now, based on the page rank your blog will show the adds. If a click of add made with a higher page rank and lower page rank differs with the amount of money. So, note that to earn money from adsense you need to have good page rank.
How to improve the page rank?
Though many people tell different ideas. The simplest idea is to write posts which are of one kind. If you start write about Life for example. Make sure that your post has a tag Life in it. So that when Life is typed in goggle search your blog pops up in the list at first pages.