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