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