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