Adding Google AdSense in WordPress
You need to determine where you want to show the ad on your website. Most commonly ads are displayed in the sidebar. You can add the Ads in your sidebar by using WordPress widgets.
Simply go to Appearance » Widgets in your WordPress admin area. Next drag & drop the Text widget to the appropriate widget area and paste your Google AdSense code in there.
From the widgets dialogue simply select the widget area that you wish to add your Google adsense code snippet. Here I’ve chosen the sidebar. This is to ensure that the content is not over-powered by the advertising.
Now cut and paste your Google adsense code snippet into the text area, add a title and save. This should now be saved throughout each post or page that uses the sidebar area.