Add a defect to a story in TFS.

1. Log into the web interface.
2. Enter a project.
3. Search for your story by number at the upper right.
4. In the modal that appears click the icon at the upper left which looks like a clipboard with a checkbox on it for a "New linked work item"
5. In the second modal that appears "Work item type" should be set to "Defect"
6. Click "OK" and then go through another few steps.... the next steps are a no brainer