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