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