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