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