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