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