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