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