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