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