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