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