How to make the right side bar move to the left side of the main page in BlogSpot without changing template
Go to layout of your blog, and then go for the link Edit html.
Now in the edit template Box you will have an Editable xml file.
Go to the
float: $ startSide;
Change the startSide part of the above to endSide and then go to
float: $ endSide;
Now save the template.