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