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