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