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