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