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