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