One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(13,14,19,22)(15,20,24,27)(16,17,21,18)(23,25,28,26)(2,4)(5,6)(7,10)(8,9)(11,12)(13,15)(14,20)(16,23)(17,25)(18,26)(19,24)(21,28)(22,27) involution — undirected(6,9)(7,11)(13,16,18,14,19,21,17,22)(15,23,26,20,24,28,25,27)(5,7,8,11)(6,10,9,12)(15,24)(20,27)(23,28)(25,26)(6,9)(10,12)(13,17,19,18)(14,21,22,16)(15,25,24,26)(20,28,27,23)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.