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