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