Go To LinkWithin.Com
And go to following options and fill this easily.
Enter Your Information
1: Enter your email
2: Enter your blog URL
3: platforms, choose blogger
4: Select number of stories
5: Now, finally Click on Get Widget! after you see this
6: Click on Install Widget
On the next page it will ask your permission to add on blogger?
7: Select your blog where you add this widget element (Select a blog)
8: Select your title (LinkWithin)
9: Finally, press Add Widget Button to do this Game.
You are Done! Enjoy this Widget. :)