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