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