How to use settings.local.php with Drupal 7? I couldn't find answer from previous questions nor drupal.org/pantheon.io.

I don't know that how to get local Drupal to use settings.local.php?

There isn't a settings.php if I clone the repo from pantheon.io nor a settings.local.php.

If i create settings.local.php file it still thinks that it as a fresh install and redirects to install.php. So it doesn't recognize that file.

Naturally, all works if I create a settings.php. Can't I just create settings.php for local development and add it into gitignore so  it won't get pushed to remote repo?
When u install drupal u need to copy example.settings.php into settings.php, after drupal installation u need to include following code in settings.php:

if (file_exists(DRUPAL_ROOT . '/' . conf_path() . '/settings.local.php')) { include DRUPAL_ROOT . '/' . conf_path() . '/settings.local.php'; }