This tutorial will explain how to install classic blogger template or html format template in blogger. As we know that classic template is using html code format to design its layout. Before we do this, it is strongly suggested to back up your old template.
1. Get new template, download it.
2. Open html file with Notepad, hit Ctrl+A then Ctrl+C to copy it.
3. Go to blogger control panel and click Edit Template.
4. Now lets go to classic template.
See at the bottom page and click Revert to Classic Template.
5. Paste the code to edit template html area.

Delete previously code and paste the new code there.
6. Time to save your new template.
Click Save Template Changes at bottom of page.
All steps are done, now test your new template. If anything goes wrong or you want to add some other customization code, just re-edit your template code.