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