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