To show your recent post on the sidebar is very easy, you just follow the instruction below then you will see your recent post on your blog sidebar. here’s the steps :

1. Login to Blogger then Chose "Layout"
2. Click on "Add page element" (chose where you want to put it) then chose "HTML/Javascript"
3. Copy the code below and put it in the "content" box.

<script src="http://www.geocities.com/uddin_81/recent-post.js"></script>
<script>var numposts = 10; var showpostdate = false; var showpostsummary = false; var numchars = 100; </script>
<script src="http://YOURBLOGNAME.blogspot.com/feeds/posts/default?orderby=published&amp;alt=json-in-script&amp;callback=rp">
</script>

4. Change YOURBLOGNAME with your blogname.
5. The number "10" it’s amount of recent post that will be shown, You can change it.
6. Click Save.

Get Try it .......