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