Preferable way is to use Composer:
```
composer require innocode-digital/wp-simple-opcache-status
```
By default, it will be installed as Must Use Plugin. It's possible to control with extra.installer-paths in composer.json.

Alternate way is to clone this repo to wp-content/mu-plugins/ or wp-content/plugins/:

cd wp-content/plugins/
git clone git@github.com:innocode-digital/wp-simple-opcache-status.git
cd wp-simple-opcache-status/
composer install

If plugin was installed as regular plugin then activate Simple OPcache Status from Plugins page or WP-CLI: wp plugin activate wp-simple-opcache-status.