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