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