If you've bought the product at Magento's Marketplace - use Marketplace installation instructions
Otherwise, you have two options:
- Install the sources directly from our repository - recommended
- Download archive and use manual installation

For developers

Use this approach if you have access to our private repositories!

cd <magento_root>
composer config repositories.swissup composer https://docs.swissuplabs.com/packages/
composer require swissup/module-easycatalogimg --prefer-source
bin/magento module:enable Swissup_Core Swissup_Easycatalogimg
bin/magento setup:upgrade