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