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