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