When you create your User Story in Trello by using the “Cards” you can add subtasks directly in the user story/card by adding a Checklist. This allows you to link subtasks to the main task or user story so that you can track dependencies, completion, etc.
To create a Checklist just click on the card and then on “Checklist” on the right hand side. Give your checklist a name and start adding the subtasks.
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