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