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