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