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)(15,21)(16,20)(17,24)(18,22)(19,23)(25,28)(26,27) involution — undirected(2,4)(7,8)(10,11)(13,15)(14,20)(16,18)(17,25)(19,26)(21,24)(22,27)(23,28) involution — undirected(5,7,9,8)(6,10,12,11)(13,16)(14,21)(15,17)(18,26)(19,25)(20,22)(23,27)(24,28)(5,8,9,7)(6,11,12,10)(13,17,19,18)(14,22,23,24)(15,25,26,16)(20,27,28,21)(6,12)(10,11)(14,23)(20,28)(21,27)(22,24) 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.