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