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)(13,14,19,16)(15,20,18,22)(17,24,26,21)(23,28,25,27)(1,2)(3,4)(13,15)(14,20)(16,22)(17,23)(18,19)(21,27)(24,28)(25,26) involution — undirected(6,10)(7,11)(14,16)(15,18)(21,24)(23,25) involution — undirected(5,7,9,11)(6,8,10,12)(13,16,19,14)(15,22,18,20)(17,21,26,24)(23,27,25,28)(5,8)(6,11)(7,10)(9,12)(13,17,19,26)(14,21,16,24)(15,23,18,25)(20,27,22,28)(13,18,19,15)(14,22,16,20)(17,25,26,23)(21,28,24,27)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.