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