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