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