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