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