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