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