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