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