Adding a "Add A Page Element" Widget To The Blog Post Main Column

Sign into Dashboard, and in the relvant blog, click LAYOUT, then click EDIT HTML. In the Template Editor, look for this block of codes:

<div id='main-wrapper'>
<b:section class='main' id='main' showaddelement='no'>
<b:widget id='HTML10' locked='false' title='' type='HTML'/>
<b:widget id='Blog1' locked='false' title='Blog Posts' type='Blog'/>
</b:section>
</div>

Look particularly for showaddelement='no' and change it to showaddelement='yes', then save the template. Click "Page Elements" to get to the LAYOUT and observe that an additional "Add a Page Element" have been added to the top of "BLOG POSTS".

Source: Blogger Tips And Tricks