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