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