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