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