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