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