1. The first way is to upload the template that had xml extension. If you do not have a template, you can download from the internet.
2. If you already have its template, you can open the blogger.com and select TEMPLATE. click on the right of Backup / restore, then click Choose File
3. Select the template on the computer then click OPEN
4. Click Upload
Sometimes it takes a lot of time to make the blog as expected because you had to work especial HTML code there. But now you do not need to do it again, because it simply follows the steps above to change the look of your blog to make it look more attractive. Now you can try to change your template blogger according to your wishes. I hope the above explanation can be useful for you.