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