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