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