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