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