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