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