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