Adding meta tags to blogger

Here is the code you have to add

 <meta content='DESCRIPTION HERE' name='description'/>
<meta content='KEYWORDS HERE' name='keywords'/>
<meta content='AUTHOR NAME HERE' name='author'/>

 Add the above code just after this [Look at the below screenshot]

<b:include data='blog' name='all-head-content'/>

Don't forget to add description and keywords.
and save the changes.