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