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