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