How Do I Assign/Delegate Tasks to a Team Member?

Just click on the icon that is located on the right side of the task and pick the user you would like it to be assigned to – 

You can only have one final responsible person for the task (task assignee) but you can add multiple people as followers for this task. They will be receiving all the updates about this task and can be helping with getting it done. You can read more about it here.