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