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