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