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