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