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