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