Nightmare is a free Blogger template adapted from WordPress with 2 columns, right sidebar and vintage style. Excellent template for blogs about art.
1. Unzip the template file you downloaded (you can use 7-zip or WinRAR for this task).
2. Go to Blogger dashboard, then Theme.
3. Look for dropdown menu and click on it. Then select Restore and click Upload.
4. Select the .xml file from the directory in step 1 and upload it. Thats it, your template should be installed.
Nightmare Blogger Template