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