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