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