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