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