1. Log in to your Wordpress admin control panel. Click 'Plugins,' then 'Add New.' If you are using Wordpress version 2.5 or earlier, enter 'AdSense Manager' into the search box and click 'Search Plugins.' If you are using a later version of Wordpress, search for 'Advertising Manager,' which is an updated version, although Adsense Manager may also work on your version should Advertising Manager not install correctly for some reason.
2. Locate the plugin you searched for in the results list, then click 'Install Now.' Wait a few seconds as the plugin installs, then click 'Activate Plugin.'
3. Click 'Settings' from the main menu bar, then click 'Advertising Manager.' Click 'Manage Ad Units,' then 'Create New Ad.' Paste your Google Adsense code for the ad unit you want to insert into the box titled 'AdSense Slots Other Networks,' then click the 'Import to New Ad Unit.'
4. Edit the settings for this ad unit. On the left, you can choose where you want the ad unit to appear, and on which sections of the site, such as the main index page, single posts or archive pages. On the right, you can add HTML code before and after the unit -- for example, to give the ad unit a colored border, float it to the left or right, or place it in its own paragraph.
5. Click 'Save changes' when you're done. Repeat this process for all your Adsense units.