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)(27,33)(28,30)(29,32)(31,35)(34,39)(36,37)(38,40)(1,2)(3,7)(4,6)(5,8)(9,11)(10,16)(12,23)(13,24)(14,19)(15,22)(17,21)(18,20)(25,27,31,29)(26,32,35,33)(28,38,39,36)(30,37,34,40)(1,3)(2,5)(4,8)(6,7)(10,17)(11,22)(12,19)(20,24)(25,27,31,29)(26,33,35,32)(28,36,39,38)(30,37,34,40)(2,6)(5,7)(9,12,15,19)(10,18,17,13)(11,23,22,14)(16,20,21,24)(25,28)(26,34)(27,36)(29,38)(30,35)(31,39)(32,37)(33,40)(1,2)(3,5)(4,6)(7,8)(9,13,15,18)(10,19,17,12)(11,20,22,24)(14,16,23,21)(25,29,31,27)(26,32,35,33)(28,36,39,38)(30,37,34,40)(1,3)(2,7)(4,8)(5,6)(9,14,15,23)(10,20,17,24)(11,19,22,12)(13,16,18,21)(25,30,31,34)(26,28,35,39)(27,37,29,40)(32,38,33,36)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.