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