Add 'Read More' Feature to blogger Automatically

1.Log in to your dashboard--> layout- -> Edit HTML

2.Click on "Expand Widget Templates"
3.Scroll down to where you see this:

<data:post.body/>

4.Now replace above code with below code.

<b:if cond='data:blog.pageType != "item"'>
<div expr:id='"summary" + data:post.id'/>
<script type='text/javascript'>
var blogID = "1287984091471788670";
function retriveSummaryPost<data:post.id/>(json){document.getElementById("summary<data:post.id/>").innerHTML
= json.entry.summary.$t + "..."}

function createSummaryPost<data:post.id/>(POSTID){ var script =
document.createElement("script");
script.src = "http://www.blogger.com/feeds/"+blogID+"/posts/summary/"+POSTID+"?alt=json-in-script&callback=retriveSummaryPost<data:post.id/>";
script.type = "text/javascript"; document.getElementsByTagName('head')[0].appendChild(script);
}
</script>
<script type='text/javascript'>
createSummaryPost<data:post.id/>("<data:post.id/>");
</script>
<span class='rmlink' style='float:right'><a expr:href='data:post.url'>Read More...</a></span>
</b:if>
<b:if cond='data:blog.pageType == "item"'>
<div id='post_body'><data:post.body/></div>
</b:if>

NOTE : You Must Replace 1287984091471788670 with your real blog ID.