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