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