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