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