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