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