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