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)(13,14)(15,20)(16,19)(17,18)(21,22)(23,25)(24,27)(26,28) involution — undirected(5,7,10,9)(6,8,11,12)(13,15,18,16)(14,19,17,20)(21,23,26,27)(22,24,28,25)(6,11)(7,9)(13,15,18,16)(14,20,17,19)(21,24,26,25)(22,27,28,23)(1,2,3,4)(5,8)(6,7)(9,11)(10,12)(13,16,18,15)(14,20,17,19)(21,25,26,24)(22,27,28,23)(5,9,10,7)(6,8,11,12)(13,17,18,14)(15,20,16,19)(21,22)(23,24)(25,27)(26,28)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.