There are a lot of articles on the web that teach readers on how to manually insert php codes/adsense scripts into different parts of blog in order to add Adsense into a blog.
For non-technical bloggers, the easiest way to add Adsense into your WordPress blog is to use an Adsense plugin, rather than doing it manually.
The AdSense-Deluxe is an easy-to-use WordPress plugin for quickly inserting Google or Yahoo! ads into different parts of your blog.
Below are the steps to add Adsense into your blog:
Step 1: Download Adsense-Deluxe plugin from the …

To sign up for your Google Adsense account, follow the steps below:

Step 1: Go to https://www.google.com/adsense/login/en_US/?gsessionid=rXNc06PGzks
Step 2: Complete the Adsense application form. Google will ask for the name of your website. If you do not have any, I would suggest that your sign up for an account with blogspot.com and obtain your Adsense account through that site. Once you have a blogspot account (e.g. myownwebsite.blogspot.com), you will be able to access their “Dashboard” screen in order to sign up for their Adsense service.
Step 3: Submit your Adsense application. …