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