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