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)(13,14,18,26,17,22,15,19)(16,21,23,20,25,27,24,28)(1,2)(3,4)(5,6)(7,11)(8,10)(9,12)(13,15,17,18)(14,19,22,26)(16,23,25,24)(20,27,28,21)(5,7,8,12)(6,9,10,11)(13,16)(14,20)(15,23)(17,25)(18,24)(19,27)(21,26)(22,28)(2,4)(7,12)(9,11)(13,16)(14,21)(15,24)(17,25)(18,23)(19,28)(20,26)(22,27) involution — undirected(6,10)(9,11)(13,15,17,18)(14,19,22,26)(16,23,25,24)(20,27,28,21)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.