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