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