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