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