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