There are templates with 1 or 2, and 3.4 columns, with different styles and different purposes of film, music business and so on. Let's say you have now found a template that suits you, the next thing you need to do is click on download and download the template on your computer antivirus scan and extract it as it is archived in a zip or winrar
Open the folder with the name of your new template you have two items are usually read-me text file, and HML document or template mean ok that's it.
Now go to the dashboard of your blog -click on Template in the upper right corner click on backup/Restore tab-First of all and most important click to download your old full template on your computer this is because if any problem appeared you can return it back .That is if there are problems with the new template you can always come back, remember this.
Now, click on Choose File and find a new template on your computer and upload -it
Blogger will ask you whether you want to keep existing widgets, that's all those extras that you added in the blog as a feedjit , clocks , AdSense etc.. If you want to keep the widget than click Keep ,Delete if not and it should be that . Click Preview to see your new blog look, if you keep the widgets then they may have changed the places where they are been before . Just go to Layout simply move the widgets (gadgets) to place you want
And that's it enjoy your new fresh look of your blog