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