With the motors all spinning the correct directions, you can now secure the ESCs so that they don't move during flight. By securing them to the booms, they won't get in the way of folding up your ELEV-8 for transport if you ever choose to do so.
Instructions:
Links
[1] http://learn.parallax.com/sites/default/files/content/ELEV-8/Tools/tool_pliers.jpg
[2] http://learn.parallax.com/sites/default/files/content/ELEV-8/Tools/tool_dikes.jpg