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