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