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