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