-Press CTRL + F and search for code like this <data:post.body></data:post.body>
-If you have found the code <data:post.body></data:post.body> then input your ad code under the code
-Click Save and then check the results.
Note:
-The code <data:post.body></data:post.body> is usually more than one, you can try them one by one.
-adjust the size of your ad with your blog page
-in case of error, parse the first ad code you
-If you want your ads to be above, put the ad code above the code <data:post.body> </data:post.body>.
pretty easy isn't it, good luck fella blogger.