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