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