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