1. Log in to blogger account and Go to Design > Edit HTML
2. Find this tag by using Ctrl+F ]]></b:skin>
3. Paste below code after ]]></b:skin> tag
blockquote { background:#c5c5c5 url(https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj56kKePx4rf2tathYWV8u6xggSOoG40Dn6qbeQNSWn7rOfft5SDnSlCDwCbzkkkdoohFBJwpsGvMNsr3q7t7fUaMTusHVjzohXcD_mYXTURW2gF9jZ3-XyNy_bk6atV4AzZZln8wCNabk-/s320/blockquote.png) no-repeat top left;
padding:10px 20px 10px 45px;
font-style:italic;
border:1px solid #000000;}4. Now save your template
5. when you want to use blockquote Write your text like below
<blockquote>Between blockquote tag
Your Text here...
</blockquote>
Replace Your Text here with any words,
6. You can use it when you making post.
Now you are done.

