If your 'Start' is (0,0,0) the 'End' is (-8,0,0), following the @Dgingrey's instructions.
Another question is that @Dgingrey includes two edges over the same line, one began at (0,0,0) and other began at (-8,0,0)
The 'right hand' rule is not an FC rule. It's a universal rule, used in geometry, physic, etc. You can read about it in https://en.wikipedia.org/wiki/Right-hand_rule.
The other 'rule' or criteria is a more specialized concept, owner of a few programs, and again it isn't an FC concept. It consists in to start your draw by the vertex with the less Y coordinate, and when there are two o more vertices with this Y coordinate (low), to select the one of them with the less X coordinate (left). The second part is to ubicate this lower left point at the origin of the coordinates (0,0,0). Nothing in FreeCAD force to you to follow this rule, but generally, it's a good strategy to improve the user orientation and sometimes avoid problems.