One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(3,7)(10,13)(11,15)(19,20)(22,23)(25,26,30,31)(27,33,34,28)(29,37,39,32)(35,36,40,38)(10,13)(14,16)(17,18,21,24)(19,22,20,23)(26,31)(27,34)(32,37)(35,40)(1,2,5,4)(3,6,7,8)(9,10)(11,14)(12,13)(15,16)(17,19,21,20)(18,22,24,23)(25,27,30,34)(26,28,31,33)(29,35,39,40)(32,36,37,38)(1,3)(2,6)(4,8)(5,7)(25,28)(26,27)(29,38)(30,33)(31,34)(32,40)(35,37)(36,39) involution — undirected(1,4,5,2)(3,8,7,6)(9,11,12,15)(10,14,13,16)(17,20,21,19)(18,23,24,22)(25,29,30,39)(26,32,31,37)(27,35,34,40)(28,36,33,38)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.