PrestaShop 1.6.x. How to install and configure template over the existing store

  1. In your PrestaShop admin panel go to  Preferences -> Themes. In top panel click the Add new theme button:
  2. Click Add file button to import a theme from your computer. Select file from the themeinstallator folder of your template package (where themexxx is the name of your theme). Click Save button: 
  3. Once the theme will be successfully uploaded, hover it and click Use this theme button: 
  4. On the next page you will see Modules to install, just click Save and proceed to the activation of the theme: 
  5. Go to thumbnails regeneration page and regenerate the images. Click Finish button to complete the installation process: 
  6. Go to Preferences -> Images section and check if all the image sizes are added. Refer to the Configuring images section in template documentation.
  7. Check the modules in Modules and Services_> Positions.  Some of them can be disabled or miss the content.
  8. Refresh the website and check your store.

Hopefully, this tutorial was helpful for you.