One vertex per element, one color per generator, with an edge from x to x·s.
(5,6,9,8)(7,11,12,10)(13,14,17,20)(15,25,16,27)(18,24,19,23)(21,28,22,26)(1,2)(3,4)(5,7,9,12)(6,10,8,11)(14,20)(21,22)(23,24)(25,27)(2,4)(6,8)(10,11)(13,15)(14,21)(16,17)(18,28)(19,26)(20,22)(23,27)(24,25) involution — undirected(5,8,9,6)(7,11,12,10)(13,16,17,15)(14,22,20,21)(18,28,19,26)(23,27,24,25)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.