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