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)(13,14,20,23)(15,17,22,27)(16,19,24,18)(21,26,28,25)(1,2,3,4)(7,8)(10,12)(13,15,18,25,20,22,19,26)(14,21,24,17,23,28,16,27)(5,7,9,8)(6,10,11,12)(13,16,19,23,20,24,18,14)(15,17,26,21,22,27,25,28)(5,8,9,7)(6,10,11,12)(13,17)(14,22)(15,23)(16,25)(18,28)(19,21)(20,27)(24,26)(6,11)(10,12)(14,23)(16,24)(17,27)(21,28) 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.