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