AdSense is an advertising network that has brought to website and blog owners an opportunity to make some money by showing text or a video on their websites. One great way to make money online is by adding AdSense to a WordPress site.
How to Add AdSense Ads to a WordPress Site
Login to your WordPress dashboard.
In new tab of your browser, Login to your AdSense account.
Click My Ads.
Click New ad unit.
Design your ad in the dialog box that appears.
Click Save and get code.
Copy the code for the ad in the dialog box that appears.
Come back to the WordPress dashboard.
In the Text editor, paste the code among the HTML for the post where you want your ad displayed.
Make sure you are looking at the Text editor, and not the Visual editor.
It will say in the upper-right corner of the editor box.