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