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