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