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