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