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