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