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