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)(15,24,26,20)(16,25,27,28)(17,23,19,21)(1,2)(3,4)(5,7,8,12)(6,9,10,11)(13,15,18,26)(14,20,22,24)(16,23,27,21)(17,28,19,25)(2,4)(13,16,19,20,18,27,17,24)(14,15,23,25,22,26,21,28)(6,10)(9,11)(13,17,18,19)(14,21,22,23)(15,25,26,28)(16,20,27,24)(2,4)(7,12)(9,11)(15,26)(16,27)(20,24)(25,28) 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.