Install and connect the Free plugin

1. Install and activate WooCommerce.
2. Upload the Free plugin ZIP from Plugins > Add New Plugin > Upload Plugin, install it, and activate it.
3. In Trello apps administration, create or select your app and configure it as a confidential OAuth 2.0 client.
4. Add the exact callback URL shown in the plugin settings. Enable the read:member:trello, read:board:trello, and write:board:trello scopes.
5. In the plugin’s Settings > Trello OAuth 2.0 section, enter the client ID and client secret and save.
6. Choose Connect Trello account and approve access.
7. Open Cards, select an order status, choose its Trello board and list, configure the card details, and enable card creation for that status.
8. Save the settings and use a test order to confirm the card appears in the expected Trello list.

Keep the OAuth client secret private. The plugin refreshes expiring access tokens automatically.