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