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