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